I don't see Britney posing for Playboy. I know she's trying to be provocative and "push the envelope", but I think that she is smart enough to not go that far.
Random hijack:
It is approx. 12:15 am on the east coast right now and I am really tired...so tired in fact that when I scrolled down the topics list they all ran together and I thought it said "Michael Jackson Being Offered to Pose for Playboy" Now wouldn't that be a centerfold to see