Go to Options >Advanced Options >Applications. Find Facebook >Hit Menu >Edit Default Permissions >Set all three to "Allow" The app works better that way and won't stop you from uploading photos to Facebook either...
I've noticed the delayed closing with the Facebook app too. You tell it to close, and for a little while you can still see it running from the Application Switcher. I have no explanation and I do not know a way to fix it. It only started happening with the most recent version. Hopefully a new one will come out soon and the problem will go away.
Never had any issues with FB, just press BB button then close? If that don't work then do a battery pull, also make sure you are closing out of all your apps correctly by the BB button then close?
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