Every other week, Gamasutra examines the most popular Facebook games according to monthly active users, looking at the top titles and developers on the social network to see who's attracting or losing players. Seven months after its launch, Zynga Slingo has seen its audience size suddenly balloon to 35.7 million players -- nearly three times more than the 13.2 million users it had just last week. Zynga titles typically experience rapid growth in the weeks and months after their debut, but it's unusual to see one of the company's games pick up like this long after the initial release. Since Zynga Slingo's userbase exploded last week, though, the slot machine and bingo mash-up has been losing hundreds of thousands of daily active players each day. Several other Zynga games have seen a lot of growth lately, like ChefVille, the most popular game on Facebook. The recently launched restaurant sim now has 46.7 million monthly players, compared to 25.5 million last week. Texas HoldEm Poker now has 36.4 million users (up from 35.5 million), FarmVille grew to 18.8 million users (up from 18.2 milion), and CastleVille saw an increase to 17.2 million users (up from 16.3 million). Most of the remaining titles on Facebook's top ten leaderboard, from both Zynga and other developers, either saw their audiences shrink or remain at around the same size over the last week. You can see the full list of the top 20 Facebook games along with exact monthly active user counts below:

Facebook Games Leaderboard

All charts and data are courtesy of Facebook application metrics and trends site AppData.