If you read the comments on our Facebook 3.2 and Facebook 3.2.1 posts, you might see that the latest version(s) of the uber-popular social networking app is having a little trouble on Jailbroken iPhones. Looks like Facebook is aware of the problems and working on a fix:
Yesterday saw the launch of Facebook 3.2 with Places support for iPhone, and today sees Facebook 3.2.1 with bug fixes and the explanation that Places is being rolled out slowly and is currently not available outside the US.
If this update solved any problems you were having, or clarified any confusion -- did it give you Places?! -- let us know!
Facebook's iPhone app has been updated to version 3.2 and, among other things, brings support for the new Places service that lets you see where your friends are and what location-based social activities they're up to. (At least in the US, when I tried it it said it wasn't yet available in my region.)