We’re now publishing leaderboards of the Facebook applications with the most daily active users over on AppData. As we have been doing posts looking at which apps have gained the most monthly active users each week, we’re going to start doing posts looking at which apps have gained the most daily active users over the course of each week.

In case you’re wondering why both measures, monthly actives shows the overall arc of an app while daily actives shows how engaging it is; engagement, as most developers already know, ties directly in to how much revenue you can make per user. We’ve also added another new metric to AppData: the number of daily actives divided by monthly actives, or the “sticky factor.” This shows you how well the app is maintaining if not growing its user base, if not its bottom line. If you want a more detailed explanation, check out this post over on Inside Facebook.

	Name	MAU	Gain	Gain, %
1.	FishVille	11,465,767	+10,102,806	+88.11
2.	Bowling Buddies	1,773,849	+1,773,849	+100.00
3.	Happy Aquarium	27,519,717	+1,712,351	+6.22
4.	Happy Pets	1,554,100	+1,543,619	+99.33
5.	Restaurant Life (BETA)	1,518,909	+1,518,909	+100.00
6.	FarmVille	65,387,640	+1,486,758	+2.27
7.	Diva Life	1,964,050	+1,153,914	+58.75
8.	Island Paradise	6,280,187	+691,148	+11.01
9.	Yakuza Lords	1,435,807	+651,758	+45.39
10.	Little Warrior	2,293,675	+441,141	+19.23
12.	Fish Life	1,760,336	+424,778	+24.13
13.	Band of Heroes	582,893	+416,575	+71.47
14.	Café World	28,707,412	+350,715	+1.22
15.	Texas HoldEm Poker	19,281,787	+330,746	+1.72
16.	Know-It-All Trivia	1,692,186	+302,250	+17.86
17.	Mobsters 2: Vendetta	4,873,850	+283,514	+5.82
18.	Castle Age	2,250,316	+261,748	+11.63
19.	Roller Coaster Kingdom	15,488,095	+191,336	+1.24
20.	Pet Society	21,827,377	+181,668	+0.83

As you can see, most of the leading apps are games. Some of the top gainers are, unsurprisingly, games that have just launched — FishVille and Happy Pets have only been out for a week or two. Still, in both cases, you can see the games sticky factors dropping as they grow larger. FishVille currently has a sticky factor of 45% while Happy Pets has a sticky factor of 53%. In other words, the more time passes, relatively fewer people are playing the game every day.

It is very hard to keep engagement up on a game (as it is with anything else), which is why it’s especially impressive to see the daily actives so high for games with tens of millions of users. FarmVille has an amazing 26.7 million daily active users, or 41 percent of its total user base — it is by far the most engaging app on Facebook, that we know of. And it’s still growing, with an increase of 1.82 million daily actives in the past week.

Same goes for Café World, which is seeing its monthly actives rate level off, relatively speaking, while its daily actives (and so, its sticky factor) have taken a recent upswing, climbing to 34% since the beginning of the month. This suggests Zynga may have recently introduced another engagement-driving feature or two, or pumped in more ads, or did some new cross-promotion.

Happy Aquarium also continues to surge, although its daily actives appear to be tracking its monthly actives at a pretty consistent 28% since last month.

Thank God, a game that doesn’t involve fish or aquariums. Frankly, Facebook feels way too much like high school. Something gets popular, and everybody does it. That is why Zoo World from RockYou is such a refreshing change. Originally discovered through the social developer’s Hug Me application, this zoo-keeping title has finally received its own stand-alone rendition that has its 1.4 million players creating their own, disgustingly cute, zoos.

The game actually starts out very similar to most Tycoon-style games. Players are granted a small patch of land with some starting animals on it and a few overly cheerful-looking patrons wandering about. They walk in, spend a little cash, look around, and walk out. That’s about all there is to it.

Starting with a small sum of cash, players are tasked with making their zoo worth more by adding new animals, concession stands, bathrooms, staff, and so on. Actually, one’s zoo is measured by a number of statistics, but is generally categorized into the total value of the zoo (based on the animals, tricks they know, and overall assets owned) and the quality grade of A – F (this consists of cleanliness, happiness of workers, parking, animals, etc.). The higher these are the better the player is doing, and the more money they earn.

Unfortunately, money seems to come extraordinarily slow if you don’t leave the game running in the background. Only $1 comes in at a time, and some of the starting stuff you need is incoherently expensive… especially when compared to other purchasable items. For example, how does a bathroom cost $4000 while a friggin’ tiger costs $450?! That’s about as cruel as charging $50 a use for a washroom at Octoberfest.

Another complaint is that players don’t seem to be able to actually control where their purchased animals and attractions go. The game just places it automatically, wherever there is space. Granted, there isn’t that much to decorate with, but it would be nice to have that choice, just to have a little more control.

It is, however, still surprisingly gratifying to see your zoo grow and evolve.

Speaking of evolution, players can actually breed animals. Sadly, this only consists of rare and ultra rare animals with the latter only purchasable with virtual currency that costs real money. Suffice to say, there wasn’t much to check out in that regard, but it certainly is a promising concept.

The game also has a wonderful, visual style. It is very simplistic, and the animals don’t even move, but with the peppy music (which does end up muted because it does not loop properly, by the way) and absurdly cute looking animals, the game is very… happy. It’s hard to get annoyed with any of the problems it has.

All in all, with the exception of denying players a means to directly customize their zoo, the complaints are relatively minor. That said, however, established companies like RockYou! should be held to a higher standard. Should the cost of items be more balanced? Yes. Should players be allowed more customization? Yes. Should the game be all in one Flash module rather than spread out amongst multiple pages? Yes. Could usability and interfaces be better? Yes. Point is, while the game is pretty good, it could be exponentially better.

Okay, okay, it’s been more than a week since FishVille first launched. We were just marinating a formal review, that’s all. Frankly, even without a formal critique, the game has seen quite a bit of action, especially with the whole scammy offers fiasco that led to their removal, altogether, from Zynga games. Nonetheless, the game is certainly getting back on track with just under 11.5 million monthly active users as of today.

So what sort of game play earns so many users? Well, a lot of the traffic is in part to cross-promotion and advertisement through other popular Zynga titles such as Mafia Wars or Farmville, but whether or not someone sticks with the game is where design comes into the equation.

FishVille is no different than any other of its ilk, regarding its core premise: Buy fish, decorate tank, sell fish, repeat. So what makes this game so different? What stood out the most to us, and as was mentioned in our recent analysis of multiple virtual aquarium apps, was that the game is just so much better in terms of usability and convenience. Everything is quick loading and simple, items can be viewed in a tank before being purchased (games like Fish World do not let you cancel a transaction it seems), and the store’s menu design doesn’t require users to scroll back and forth through a selection just to go back to a main page (some similar apps utilize a “Go Back” button that is only on the first page or at the top of a category).

Unfortunately, and despite good design, there aren‘t exactly many categories for this design to make use of in the first place. The general lack of categories, means that there is a lack of selection in regards to decorative items. This has often been the case for Zynga games (such as Café World) when they first release. They do eventually add more, but sometimes it does feel like procrastination: “Oh, we’ll just do it later.”

On the plus side, the game integrates the whole leveling concept more with the tasks one must complete every day in game. Other fish games grant experience simply for selling fish or cleaning your own tank. Everything you do in FishVille, on the other hand, earns you some experience; whether it is buying fish, selling them, or decoration. Frankly, the only thing that doesn’t give experience seems to be feeding the fish. Either way, it’s a minor reward that really makes players feel they are accomplishing something. Granted, it isn’t a gifted decorative item or new fish, but if a user feels they are progressing, they are more likely to keep playing.

The game also has greater integration into social play. Beyond simply feeding treats to your friends, players can also help out their neighbors’ tanks by fixing random problems that may occur (such as the tank overheating).

The last point worth touching on is the presentation. The sound effects work, but the music gets very repetitive very quick and tends to end up muted. Visually, the artwork is fantastic. Beautiful and colorful fish and aquatic items liter this game with wonderful vector graphics. However… the praise is quickly killed by the animations. The fish do not feel like fish at all, just cut-outs that dart about. They don’t move like fish; when they turn, you can tell they are flat; their fins don’t move at the rate they are swimming; and when they move up and down they rotate on their center axis, which, more than anything else, completely shatters the fourth wall and any suspension of disbelief.

Okay, so it’s a Facebook game, but a virtual aquarium should still feel like an aquarium in some way. Games take you away from reality, if even for a moment. They take you to their reality, and issues like this completely destroy it.

Nevertheless, FishVille is a well made game at its core. If anything needs to be fixed, it is animation and an increase in the variety of items. It is easily, the most usable of any of the fish titles, which can be accredited to the extensive experience Zynga all ready has. Quite frankly, and despite complaints, with over 9 million users, the company has to be doing something right. Right?

LOLapps, a developer of Facebook apps and games funded by Polaris Ventures, got its start building a white label quiz and gift creation platform for Facebook users. Since then, however, it started developing its own original Facebook games, which have been moving up the charts recently. Today, the company’s new strategy is being revealed: LOLapps has productized its Facebook role-playing game platform, and is partnering with large developers to bring their IP onto Facebook.

The first such partnership is with Atarti’s Cryptic Studios, who is working with LOLapps to create a social game version of Champions Online for Facebook. The original Champions Online MMO was released on PC on September 1st, and retails in the US for around $40. The Facebook version launches today.

According to Manu Rekhi, head of product and marketing at LOLapps, Cryptic partnered with LOLapps both to introduce the Champions Online brand to Facebook users with the intent of leading them to the paid version of the game, and to monetize through virtual goods.

“This becomes a very good funnel for them,” Rekhi told us. “Players are already immersed in their character and the game. They can either pay to level up or go download the game. Instead of getting users to sign up for Netflix, you get users to buy the game. It’s a win-win-win for users, Cryptic, and us. We’re making the original pie bigger, and creating a new pie too.”

According to Rekhi, the game was produced in a matter of weeks. Once the deal with Cryptic was signed, LOLapps’s writers and designers applied the Champions Online story line and theme to its RPG platform, while being very conscious to take care of the Champions brands.

Because LOLapps is not a custom shop, they don’t have to charge partners anything to launch the game, something Rekhi says is music to developers’ ears. Rather, LOLapps games can monetize through driving incentivized sales of downloadable games, or by virtual goods inside the Facebook game itself. It all depends on the partner and the rights they have to the IP. And, because of its network of white-label quiz and gifting apps, the company can drive distribution itself as well.

Fundamentally, Rekhi hopes the LOLapps model can help reduce the hit-driven risk of the games business by driving more demand for games.

“If you can reduce that risk from 1/10 to 1/7 or 1/5, that’s huge value that our partners can get out of this. They can funnel all their users to a game that’s being launched three months out, drive pre-sales, and show purchase intent [in a LOLapps version of the game]. That would have been harder to do before,” he says.

“A lot of [larger developers] have tried building their own games, or going through agencies, and failed. They don’t really understand how things work. When you go in and say not just we can build it, but we can make a variety of interesting things happen within it, it actually gets pretty easy to convince them. If it doesn’t work, they lose nothing.”

To assist in the development of its social RPG platform, LOLapps acquired MMO games studio ROFLplay in July. They bring a “very strong Asian influence, as you can tell by Yakuza Lords,” Rekhi says. The company’s second game, Diva Life, was a departure from Yakuza’s storytelling style. Rekhi says its platform enables the company to quickly roll out new features in one game or another.

“What Facebook has done is really amazing – all your friends are already there. Kudos to Facebook for mapping the social graph,” Rekhi says. “The traditional large customers just take a lot longer to really see what the value is there, so we’re filling the gap.”

There are a couple dimensions to Zynga’s new $15.2 million funding. One is time. VentureBeat and peHUB reported the company’s latest regulatory filing earlier today. But, we heard rumors about “another round” of some sort that it was raising, back in April of this year.

One source, who previously said Zynga had raised money in late June, has reiterated that point to us now. Meanwhile, Zynga has denied a new round of funding or not commented, at least up until today.

The filing shows that it was an extension of an existing round. That’s one of the ways that the company could have credibly denied a “new round” up to this point.

In terms of investors, the money apparently came from existing ones, as the filing — a legal document that the company has to submit to the government about any fundraising activity — doesn’t list any others. Zynga’s investors include: Kleiner Perkins, Foundry Group, Avalon Ventures, Institutional Venture Partners and Union Square Ventures, who together have put in $4o million to date; we have more recently heard that Zynga’s banker has been Allen & Co., and earlier this year the company was intending to raise a round worth between $500 million and $600 million.

Getting the Full Picture

The other dimension is space — between how much the company is rumored to be making and what its valuation is. We hear the valuation is around $625 million, although the company isn’t telling us anything beyond confirming the filing. We have heard various rumors about Zynga’s revenue, with the number increasing over the course of this past year to $50 million, then $100 million, then $200 million. These days we hear far more incredible rumors, that we’re not confident enough about to publish here.

The two dimensions reveal more about what Zynga’s funding situation probably is: Old news.

That’d be back before it saw massive growth with games like virtual farm game FarmVille, then virtual restaurant Café World and most recently virtual aquarium FishVille. While those sorts of games are often considered within the industry to make less money than older titles like poker, role-playing mafia games, and other early Zynga titles, the new ones have also gotten even bigger. And, each clearly monetizes through getting many users to come back every day and play, and buy virtual currency or earn currency through advertising offers. It is no suprise that revenue rumors keep going up. Note: The presence of scammy offers, their removal, then Zynga’s decision to remove all offers for the time being, mean the company could possibly see a revenue drop, or at least slowdown — it has said that a third of its revenue comes from offers.

There is also the matter of profit. How much more money is Zynga bringing in than paying out? The company doesn’t say how it spends its money, of course, but millions are visibly spent on advertising within Facebook, like the FishVille ads that have been everywhere for the last few weeks. If the new funding did come in June, we’d be interested to know how it helped spur FarmVille’s massive growth over the course of the summer, or what key acquisitions it might have gone towards.

Until the company clarifies when this funding happened, we should not conclude that it is new. As a result, if the valuation of $625 million is months old, we can only assume that Zynga is worth far more now. Possibly as a result of these reasons, we heard rumors earlier this fall that the company had been talking to Electronic Arts about an acquisition with an asking price of around $1 billion. Instead, as it turned out, EA bought Playfish in a deal worth up to $400 million — while Zynga appears headed to an initial public offering.

[Zynga billboard image via Hiten Shah]

As expected, November 17th is indeed the day that Xbox Live goes social with its latest big update. The popular online console service now has integration into leading social sites Facebook and Twitter.

Currently, the integration for Facebook is not the complete version, so you won’t be playing any FarmVille on your high definition television. However, the Live rendition does incorporate all of your major Facebook site features. From your TV, you can view pictures (which was a personal favorite), see updates, and post to your feed. Granted, it is a bit obnoxious to type with a controller, and not a keyboard, but it is still pretty cool from what we’ve played around with so far.

Another interesting feature is that you can see all of your Facebook friends who are on Xbox Live and all of your Xbox Live friends who are on Facebook (once they have installed it on their console). Of course, this doesn’t mean that your normal Facebook friends list is forsaken. On the contrary, you can see all of them and view all their updates, news feeds, and pictures right from your couch. It’s nothing different, really, from what you can do on the web… except the whole 1080i thing.

> Continue reading on Inside Facebook

Hailed as one of the most difficult video games ever, the franchise of Ghosts n’ Goblins/Ghouls ‘n Ghosts, staring our good friend King Arthur, has been the bane of gamer existence ever since its inception. However, the latest in Capcom’s series, Ghosts n’ Goblins: Golden Knights for the iPhone and iPod Touch, places the Japanese console developer onto the ever growing list of mainstream game makers adopting virtual goods.

For those unfamiliar with the series, Ghosts n’ Goblins and Ghouls ‘n Ghosts are games in which the player may only be hit twice before it’s game over, as they attempt to rescue fair maidens. Hit one takes off all of Arthur’s armor, down to his skivvies, and hit two takes him out. With the side-scrolling world wrought with baddies, however, trying to survive is, suffice to say, quite difficult. In the 80s alone, its arcade rendition ran kids’ and parents’ wallets dry.

Well, in light of that difficulty, Capcom decided to do the only logical thing it could with this classic franchise. Make it easier! Okay, maybe that’s not exactly what they did, but rather, they introduced some minor virtual goods that can. For $0.99 players can purchase a super-item called the “Golden Armor.” The item grants some pretty hefty magical attacks that make the game significantly simpler. Of course, the item can be earned in game, but here’s the catch: If you take too much damage it goes away. The purchased version, on the other hand, does not. As it would seem, the power of money is much greater than any medieval demon spawn. In addition to the armor, players may also purchase other power-ups such as unlimited lives (for the same dollar price).

According to Virtual Goods News, while Capcom may be new to virtual goods, this is not its first dance and are moving more and more into this business model. It had already dealt with the sale of extra levels, difficulties and characters, and even closed a deal with virtual goods company Virtual Greats regarding the title Street Fighter IV. Furthermore, its branded virtual goods within PlayStation Home consisted of items from the aforementioned fighting game as well as Resident Evil, which have sold more than 200,000 units in roughly two months, according to Sony Computer Entertainment of America chief executive Jack Tretton. While it is unlikely that the new iPhone virtual goods for Ghosts ’n Goblins will do as well, you can bet that we will be seeing more virtual goods come out of the developer in the coming future.

When you get purchased by someone as huge as Electronic Arts (EA), there is definitely a bit of turmoil as everyone tries to understand how the two companies will co-exist and work together. One of the more interesting things we’re seeing is a decline in daily active users (DAU) across the top Playfish titles since the acquisition last week.

Although Pet Society is down only 2.4%, Restaurant City is down 6.8% and Country Story is down 10%. While Playfish COO Sebastien de Halleux noted that “EA gives us more resources to grow right now – more marketing budget to reach new users in new ways,” it doesn’t look like the initial push is to try to match Zynga’s aggressive advertising to grow the user base on Facebook.

Indeed, if you listened to the EA quarterly earnings call discussing the acquisition, EA management clearly saw the Playfish as a way to “open up doors to folks that aren’t console players” and upsell their IP. This manifested itself shortly after the announcement, with Playfish titles like Pet Society and Restaurant City running cross-promotions of EA’s Pogo.com casual game portal and the Sims 3 iPhone application.

While it is very possible that these cross promotions helped drive daily traffic away from Playfish titles, you also have to wonder if the Playfish team has cut back on some of its advertising so that it can begin to coordinate efforts with EA.

Pet Society Introducing More Game-Enhancing Virtual Items

Amidst the turmoil, the product teams at Playfish continue to roll out new features, the most interesting being a Nannybot in Pet Society. The Nannybot looks remarkably like Rosie the Robot from The Jetsons and allows the player to have the robot clean (via shower attachment), feed (popping toast via a toaster into your pet’s mouth), and play (tickling your pet with a giant feather) while they are not online.

To date, the majority of items in Pet Society have been vanity items, allowing the end-user to express themselves by dressing up their avatar or decorating their house. But there is a natural limit to the number of vanity items a user can use at one time – there’s typically only one avatar and only so many rooms in your house. Playfish has tried to address that, adding hangers and shelves so you can show off more of your clothing collection (launched September 12th) and launching the ability to add even more rooms to your Pet’s house (October 25th).

Another way to break through those limits is to focus on what I call game-enhancing items, designed to help the player achieve something or mitigate the grind in the game. While Playfish has had some game-enhancing items in the past (like fruit trees that grow food so you don’t have to constantly spend coins to buy items to beed your pet), it has recently been rolling out a steady stream of these items in its cash shop:

• Special fishing hat (September 28th), glove (October 5th) and vest (October 12th) that help you catch more rare fish, and
• Pro shoes (November 2nd) to help you avoid slipping on the ubiquitous banana peels in Stadium races
• Pro vest (November 9th) to help you better jump the hurdles in Stadium races

The Nannybot is the most recent addition and works very similar to the tractors and other farm equipment in FarmVille – the equipment or nannybot is nominally expensive, but you have to pay real cash for additional fuel for the farm equipment or batteries for the Nannybot. The Nannybot batteries last three days, long enough for someone to escape for a long holiday weekend and not worry about their pet.

Clearly Playfish is focusing on figuring out how to extract more value from their strong relationships with users. To illustrate that point, John Earner, the company’s vice president of product, recently noted that 50% of the users that have installed the Pet Society application since launch are still active in a given month. And while so far the EA acquisition hasn’t jump-started an acquisition campaign — Playfish has repeatedly stated their strategy is to run a marathon while competitors are focusing on sprinting for market share — the focus on virtual items that enhance the user experience could have an equally positive impact on the bottom line.

Eric von Coelln was the vice president of marketing at Oberon Media, a leading multi-platform casual games company, and most recently the vice president of Marketing at PowerSoccer.com. He is now a New York based freelance consultant to games, e-commerce and social media companies — including some of the largest social gaming companies on Facebook. While Mr. von Coelln does write about some companies for which he has done paid consulting from time to time, this post is based on publicly available information and in our view is an unbiased analysis of the industry. You can find his blog here.

Last week was notably good for smaller games and game developers, juding by our top 20 growing apps list. The most obvious “small app” is Zynga‘s FishVille, which we’ve covered separately as it grew by an impressive 8.24 million monthly active users last week to reach 9.24 million.

Considering FishVille is from the largest developer on the platform — and the one with the most cross-promotional power as well as money for advertising, let’s take a look at some smaller ones. Next on the list is Happy Aquarium from CrowdStar, a relatively small developer but an already-big app: It gained 1.93 million to reach 27.0 million monthly actives, on the same trajectory as pst weeks.

	Name	MAU	Gain	Gain, %
1.	FishVille	9,238,698	+8,237,776	+89.17
2.	Happy Aquarium	27,054,550	+1,930,762	+7.14
3.	FarmVille	64,606,716	+902,322	+1.40
4.	Diva Life	1,589,777	+796,317	+50.09
5.	Island Paradise	6,085,569	+750,521	+12.33
6.	Little Warrior	2,324,123	+674,042	+29.00
7.	Yakuza Lords	1,229,559	+468,293	+38.09
8.	Farmville Gifts	427,577	+401,200	+93.83
9.	Fish Life	1,611,848	+389,427	+24.16
10.	Texas HoldEm Poker	19,201,295	+323,468	+1.68
11.	Snowball Fight	335,255	+303,988	+90.67
12.	Roller Coaster Kingdom	15,426,497	+302,012	+1.96
13.	Band of Heroes	436,604	+293,784	+67.29
14.	Mobsters 2: Vendetta	4,774,524	+280,863	+5.88
15.	Castle Age	2,167,708	+262,495	+12.11
16.	Snowball Fight!	548,043	+228,216	+41.64
17.	Pet Society	21,813,174	+209,564	+0.96
18.	Piou Piou contre les cactus	274,005	+177,025	+64.61
19.	Rock Riot	1,330,683	+167,895	+12.62
20.	The Hierarchy	265,700	+166,586	+62.70

At number four, we have the first of three games on today’s chart from LOLapps: role-playing game Diva Life, which grew by 796,000 last week to reach 1.59 million monthly actives. LOLapps has been cooking up a range of RPG games lately, with Yakuza Lords and Band of Heroes also appearing further down on today’s list. Note that the latter two also made our up-and-comers list last Friday; that list looks at the top growing apps with between 100,000 and 1 million users, so clearly, and Yakuza Lords has since moved up into the AppData big leagues. On a design level, these games distinguish themselves not so much through the game mechanics but by having slick images and story lines, which something that cannot be said for some of the other RPGs on Facebook.

Down the list, we have Island Paradise, a farming-style simulation game from Neopets creator Meteor Games — it also showed up last week. And, we have Little Warrior, a basic arcade-style game that also showed up last week.

And another interesting one is FarmVille Gifts, which contrary to what the name suggests, is not made by Zynga. Instead, the app lets you send FarmVille-themed gifts to your friends but “NOT,” as the app makes clear, to your friends in FarmVille. This looks exactly like a trademark violation, to say the least. As we noted when we spotted the app in our up-and-comers list last week, we’re surprised it has not been shut down yet.

Finally, Slide’s Rock Riot and Serious Business’ The Hierarchy have both pushed their way on to the list.

It’s not totally clear what Zynga has been feeding FishVille, but the results are now obvious: The virtual aquarium application has reached 9.24 million users, according to AppData. The game actually launched early this month, but wasn’t being promoted through Facebook advertising or on Zynga’s toolbar until the 8th or so, from what we can tell.

But what a past week this game has had. FishVille was taken offline for 36 hours last weekend because it was running rule-breaking advertising offers — and once it came back online, its traffic actually lurched downward. We wondered if Zynga had turned off advertising for the app at some point last week, given its lack of growth. The ads, or whatever Zynga has been doing, are back, because lately it has been gaining millions of new users every day.

If there was any question that Zynga might not be able to follow its hit games FarmVille and Café World with a new one, forget about it. Virtual aquariums are the latest popular genre of game — we now count six with more than 1 million monthly actives, led by CrowdStar‘s Happy Aquarium, which has 27 million monthly actives. Zynga has a history of building games that closely follow existing hits from other developers, then adding its own variations on the game mechanics and combining all that with its formidable active user base and advertising warchest. With FishVille, this formula appears to be working once again.

And that’s despite Facebook tweaking the news feed that the company optimized some of its game-play around, like getting users to share actions from a game into their feed. While there’s a long list of potentially handicapping changes coming from Facebook in the next couple of months, Zynga’s “playbook” for hit-making is for now doing just fine.