Move over, FarmVille. You've got a new neighbor...a more successful one; one that has already become the most popular place in the 'hood. On Christmas Eve, 2010, CityVille, Zynga's latest social gaming creation, became the top app on Facebook, according to AppData. It displaced the long-standing, ever-popular, competition-resistant, first-on-the-block FarmVille. On December 24, 2010, CityVille logged 61.7 million monthly users, beating FarmVille by almost 5 million users. What makes this even more stunning is the fact that CityVille had been launched only three weeks before. That's right. Three weeks.

In this latest "Ville" game developed by Zynga, there is a distinct flavor of Sim City because you build your own city from scratch. In this game, you have the ability to start businesses, create services for your citizenry such as post offices, schools, fire and police departments. And, the more community buildings you erect, the happier your residents are, which then increases your population. You can buy and sell services and products with other cities. And, in a departure from FarmVille, you can create services and build franchises in your friends' cities. In fact, as you build the same franchise in more of your friends' cities, your headquarters building grows taller. And, you can invite your friends to put their franchises in your city. The success of game play for you depends on the number of "neighbors" you have (meaning, the number of friends you have who are also playing the game). If you don't have any friends who play, you can acquire them in a number of ways. (The best and easiest way to do this is to go to CityVille's Facebook page and add people who have "liked" the game). The more friends you have who play the game, the more fun it is for you. Some analysts believe this game is Zynga's "most complex" game in terms of graphics and mechanics. But, besides the game's technical proficiency, it is, as Sean Kelly, General Manager of CityVille puts it, "...Zynga's most social game to date."

The amazing news of CityVille's success becomes even more astonishing when you consider the fact that, since FarmVille's debut, Facebook has changed its policies from its nascent days and has shut down the "viral channels" that game developers were using to gather potential gamers. (Facebook stopped this practice in order to put an end to those annoying spam-like updates from numerous social games.) So, when CityVille made its debut, it did so without the launching methods that helped make FarmVille such a massive hit. However, Zynga was able to cross-promote CityVille to its FarmVille users and that was an important piece of CityVille's success story.

When CityVille launched, it set a first-day record of 290,000 users, making it the largest opening day of any game in Zynga's history. Since that time, the game is experiencing daily growth of 7 million users a day and a base of 16.7 million active users per day. And, there are no signs of CityVille fatigue. This has to be good news for Zynga, as the company has seen a decrease in active users across most of its social games, dipping below 200 million monthly active users for the first time in a year. Interpret games analyst Michael Cai says, "I think the gold rush [in social gaming] is pretty much over now, the days of easy money are gone...The growth from this point on is going to be more organic than explosive." Cai also believes that user growth of social gaming in the US may have leveled off permanently, saying that it's doubtful that any future social network games will reach the success of FarmVille or CityVille. My unofficial survey of CityVille players seems to confirm Cai's analysis. I could not find anyone under the age of 20 who actively plays CityVille; of the people in my circle who play this game, they are adults with far fewer Facebook friends (in the hundreds) than those Millenials (whose friends number in the thousands!). So, while there are obviously people out there playing the game, how long will CityVille's popularity last if those playing it have fewer friends?

Nevertheless, Zynga has a right to be optimistic about its latest game's success. On its record-setting launch, Zynga says that the growth was an organic one as most of the 290,000 users came from players who invited their friends to play or posted about the game to their Facebook friends. Zynga had not yet begun cross-promoting the game, so this explosive launch would probably have been much bigger if it had. However, it should be noted that Zynga did one thing that made game developers take notice: the company launched the game internationally. For the first time in Zynga's history, it launched a new game in five different languages (English, French, Spanish, Italian and German). Because social games are maturing (and, as Cai theorizes, leveling off), games analysts believe that international and mobile markets are the best channels for success in social gaming. CityVille's successful launch seems to prove that point exceptionally well.

Readers, were you one of the 290,000 who signed on to CityVille upon its launch? Do you play the game now? If so, what do you like about it?