Zynga is on the verge of launching CastleVille, its latest life simulation game for Facebook and the first title from the Zynga Dallas studio formed in 2010.

We got an early look at the game during Zynga’s Unleashed demo event in October where Zynga Dallas Creative Director Bill Jackson showed the audience a trailer and described the game as massive in both size and scope. Jackson follows up this month with a hands-off press demonstration showcasing roughly the first 15 minutes of gameplay and the neighbor-visiting mechanic.

In CastleVille, players take the role of a man or woman tasked with exploring and clearing a forest in order to build a thriving castle town. The core gameplay loop is similar to FrontierVIlle more so than FarmVille, where players perform a broad range of industry-related tasks (like farming or animal husbandry) and exploration tasks (chopping down trees, etc.) in order to earn experience points, virtual currency, and items. Monetization comes mainly in the form of purchasing energy refills or items like buildings or decorations. As the player progresses in building up the town and opening up new areas of the map, new non-playable characters become available for the player to interact with and receive character-specific quests. There are also “beastie” non-playable enemy characters that the player has to fight off in combat, similar to the critters in FrontierVille. Social features planned for the launch are limited to visiting friends’ kingdoms to help perform various tasks, including fighting off beastie attacks.

One of the key instances where CastleVille differs from we find in FrontierVille and CityVille is in depth of NPC interactions. Like other ‘Villes, NPC characters in CastleVille carry specific quests the player can complete for more rewards. To meet these NPCs, however, CastleVille players have to unlock certain sections of the map using resources — and these sections may or may not contain an NPC. Given the size of the land to explore, Jackson says it is possible for two different players to have two different casts of NPCs in their kingdom. Moreover, additional characterization and animations have been added to the CastleVille NPCs where a character might idly perform a certain action if left alone for a while — or even interact with specific items that the player as placed in their kingdom. For example, the macho Rafael character has a push-up animation that displays randomly, and he may be able to interact with archery butts that the player can place in their castle town.

In this screenshot, we see yellow arrows indicating plants that need watering and animals that need tending, while coin icons indicate buildings that can be harvested for resources. A rat in the upper right hand side of the screen is a “beastie” that the player can attack.

A second instance is in the reputation system. In FrontierVille, CityVille and Empires & Allies, reputation functions as a level independent of player level that increases as players visit and help (or attack, in the case of E&A) other players they’ve accepted as neighbors. CastleVille changes the formula by making reputation into a currency that players earn by visiting and helping neighbors — and then can spend on special items like topiary decorations. This brings the total number of currency types in CastleVille up to four: reputation, coins, gems, and castles. Reputation and coins function as soft currency whereas gems are a premium currency that can sometimes be earned through gameplay (like other Zynga premium currencies) and castles are awarded based on how many buildings or decorations the player has placed in their kingdom.

A third key instance is in the player’s ability to alter their kingdom layout. Currently, FrontierVille, CityVille, and Empires & Allies players cannot restructure the layout of their towns without painstakingly moving individual items — buildings, bushes, roads, etc. — and then rearranging them in a way that meets gameplay objectives (e.g. getting a collection bonus by having a row of flowers alongside a building in CityVille). Though we were not able to see this at work in the demo, Jackson says that players can click and drag the center of their castle town (the courtyard, is what he called it) and all walls that the player has constructed around their castle will adjust to fit. All bodies of water can also be dragged to create moats, ponds, rivers, or lakes however the player wants to structure them.

Aside from that, it’s the little things that set CastleVille apart from its ‘Ville siblings and from other games on Facebook. The quality of the art and sound is much higher than most of what we’ve seen in 2011, and additional animations — like the wobbling of a tree as it’s chopped or fish jumping in a pond — add a layer of depth to the game. Minor gameplay tweaks to traditional ‘Ville gameplay reinforces the feeling; for example, if a player plants crops beside a body of water, the animation of the crop changes to reflect irrigation and that crop happens to grow faster than those planted away from water (see crops around the pond in screenshot below).

Given the use of mechanics well-explored by FrontierVille, CityVille and even Empires & Allies, CastleVille is well-positioned to experiment with new content as the game gains players after launch. Already, Zynga Dallas is planning to add a trading system post-launch where players can exchange in-game goods in a marketplace setting. Additionally, Jackson said there may be room to add player-versus-player combat or adapt the existing player-versus-environment combat to a larger scale that could encompass cooperative multiplayer. It seems to be the developer’s intention to make CastleVille resemble a massively multiplayer online role-playing game more closely than any other Zynga game has so far.

CastleVille launches “in the next couple of weeks,” according to Zynga. A spokeswoman said that the timing of the release was in no way affected by Zynga’s impending IPO.