In a blog post yesterday, Facebook announced new features and improvements to its mobile application Facebook Messenger. The new update allows users to see who is online, who's on mobile and when the other person is typing.

New support has been added for 22 new languages on Android, and 12 new languages on iOS. Facebook Messenger is already available on iPhone (including iOS5) and Android, and now it's available on BlackBerry. Beluga, the system behind Facebook Messenger, was supposed to be the BlackBerry Messenger for non-BlackBerries. In an ironic twist of fate, that system has made its way to BlackBerry through Facebook.

The launch of Facebook Messenger this past August was yet another step toward a unified communications platform for Facebook, giving users the ability to communicate with both Facebook friends and their phone contacts without having to decide which device or platform to use.

Now that this app has come to BlackBerry, will BlackBerry users start leaving BlackBerry Messenger for Facebook Messenger?

As with Facebook Messenger for iPhone and Android, the BlackBerry version brings in all of your Facebook conversations, making it easy to access everything from one place. The app stands alone. BlackBerry Messenger offers messaging with other BlackBerry Messenger-confirmed users only.

The announcement about Facebook Messenger came from Facebook engineer Lucy Zhang, ex-Googler and co-founder of the group messaging startup Beluga, which was acquired by Facebook in March, right before SXSW. As it expands, Facebook Messenger continues to build off Beluga's design - and this isn't the first time Beluga has been compared to BlackBerry Messenger.

Calling all BlackBerry users! Do you have BlackBerry Messenger? If so, would you be willing to switch to Facebook Messenger?