With the FIFA World Cup set to kick off this Friday, we’re seeing an explosion of activity from social game developers. Dozens of new soccer games have appeared over a span of weeks, each hoping to ride the wave created by the world’s most-watched sporting event.

Here in the US, it’s sometimes easy to forget that soccer (or, everywhere else, football) is by far the world’s dominant sport. Worldwide, some 250 million people play football. The fan base likely runs into the billions.

But game developers, especially those working on social games, are increasingly looking to international audiences — that is, if they’re not international themselves. Below is a quick view of four familiar names with recently-released soccer games:

Note that traditional media seems eager to get in on the action — each company has a high-profile partner, although Playdom’s partner is working didn’t work with Three Melons on Bola and Fantasy Moguls only has CBS Sports along for a newer title, Galacticos South Africa. There are also special sponsorships to consider, like Playdom’s deal with National Geographic.

Bola has a clear lead for the moment, gained with the help of its early launch date. But it’s unlikely that either EA or its partner FIFA is aiming for just a few million players; at least some of the companies working on soccer games today are undoubtedly hoping to create a FarmVille-sized hit, based on Facebook (or the iPhone’s) worldwide growth and the huge, nascent soccer fanbase.

The question is whether any will be capable of making it to that point. Despite the huge marketing push for the World Cup — South Africa, the host, has been preparing for years — we simply aren’t seeing players stream into soccer games yet.

Part of the problem may be the relatively complex approach these games take. EA, being affiliated directly with the worldwide football association, would seem to have an unbeatable advantage. The characters in the game are actual players that fans will recognize, and the FIFA brand name has made console games successful.

Yet EA (through its acquired development studio, Playfish) chose to go with a team management style that requires some knowledge, and a fairly deep level of participation, from players. An audience of people that might appreciate this exists on Facebook: so-called “spreadsheet gamers”, who calculate out how much each game activity will earn, usually in farming games. Unfortunately, this group of people is probably relatively small.

To be clear, FIFA Superstars wouldn’t be considered at all complex on a console gaming system — but Facebook is a different world. Fantasy Moguls, also, has chosen to make management oriented games, and Galacticos Football has over three hundred thousand MAU to show for it. But the audience for a management title may not be much larger than that, at least for now.

Playdom and Watercooler have gone a somewhat different direction. While EA’s FIFA title shows a well-made animation for each game, players don’t actually have any direct involvement in the matches. Both Bola and Epic Goal, by contrast, are live-action titles.

The catch is that this also isn’t a proven category on Facebook. In our review of Epic Goal from just a few days ago, we noted that Watercooler tried to account for relatively inexperienced, casual players with slow-moving, childlike characters and bright colors. Luckily for Epic Goal, the action category has been somewhat pioneered by Bola, which we found can actually be quite difficult.

The total MAU of these four games — not to mention several more we didn’t have room for in the chart — doesn’t even amount to five million players, even with soccer enthusiasm presumably at a fever pitch. We’ve also reviewed iPhone soccer games, like Gamevil’s newly-launched Soccer Superstars, but at present there’s not a single soccer game among the top 50 paid or free games for either the iPhone or iPad.

Nevertheless, we’ll keep looking at soccer games as they appear during World Cup, just in case one is the next big hit.