Facebook for iPhone not playing nice with Jailbreak, fix coming soon
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:
If you have a jailbroken device, you may have experienced problems with our latest updates. We've identified the issue and have an update with a fix coming soon. Thank you for your patience.
BiteSMS for Jailbreak is often mentioned as a source of conflict. Until the fix is pushed out, you can uninstall it to get Facebook working, or just use touch.facebook.com to get your social on.
[Facebook, thanks Robert!]