Some people do have 2.0 installed on their v1 iPhones but everyone who has tried the FaceBook app has said that it is not connecting. Maybe FB just hasn't started allowing connections through their app yet and plan on it tomorrow for the official release.
I'm glad everyone else is having the same issue, I freaked out for a minute thinking my v2.0 was bad or something. Has anyone tried downloading 'AOL Radio'? That doesn't seem to be working correctly either.