Phrases has managed to knock out FarmVille as the most popular app on Facebook. The Phrases app, which allows users to post random sayings, quiz results and images, to their friend feed, now has 54.3 million monthly users, which only barley caps the 53.9 million monthly active users of FarmVille.

Phrases is not likely to stay top dog for long, since access to it was recently pulled for U.S. based users, by Takeoff Monkey, the creators of the app. This has resulted in a rapid drop in the app's daily active users count, according to Inside Facebook. No reason for cutting off U.S. based users was given. On the site the message simply states, "Sorry, currently Phrases can't be accessed from within the US. We've had to make this tough decision in spite of the support of our fans in the US. Currently we have no timeline for lifting this restriction." FarmVille, which has been in the top spot since August of 2009, so it is likely to take the top spot again soon.

The company that makes FarmVille, Zynga, is also the creator of five of the top seven most popular apps on Facebook. Titles such as Texas HoldEm Poker, which has 35.4 million monthly active user, FrontierVille, which has 28.9 million monthly active users Mafia Wars, which boasts 22.3 million  monthly active users,  and Cafe World, which has 17 million monthly active users. All of these games large user bases contribute to the company's 360 million monthly active user count.

Zynga, which was founded in January of 2007, is also planning to launch a new title CityVille, which will feature localization of buildings end user can choose from. The beta version of the app is expected to be released in the next few weeks.

Takeoff Monkey was not available for immediate comment.

(Image from Zynga)