Zynga's new game Cityville has become the most popular Facebook game to date, surpassing its own game Farmville in the process. There are now 16.8 million people playing Cityville every day. Farmville, by comparison, has 16.4 million. Other Zynga titles Frontierville and Texas HoldEm Poker also rank in the top five.
On a monthly basis, Cityville now eclipses 61.7 million players, while Farmville has 56.8 million.
The only game to make that ranking that wasn't a Zynga game is a game called Phrases, which places #3. In other words, when it comes to Facebook games, it is still really only about Zynga.
In fact, when looking at Zynga's top four games in aggregate, it has 184 million active users every month. That's the equivalent of more than half the population of the United States.
The social gaming giant has begun expanding to the iPhone and, recently, Android. These mobile games let players keep tabs on their Facebook titles, with integration between the social networking site and the mobile game. Zynga doesn't want you to stop playing just because you're not at a computer screen.
We haven't heard anything about Zynga going to bigger platforms like the Xbox 360 or PS3, but it's probably just a matter of time.