I would have told you right here and right now, but some people apparently consider it a spoiler (I don't, but respect those who do). So I must emphasise, only read the rest of the post if you don't mind knowing what celebrity appears in the game (I won't disclose any information regarding story lines, where he appears or anything else).

Rick Gervais. This will be more of a big deal to us Brits, but I have talked to some Americans on the matter, and they also seem to enjoy this news. I won't reveal anything else, but this is pretty cool. Ricky Gervais is a well known comedian in Britain, who has also done work in America, he wrote 'The Office', 'Extras' and an episode of 'The Simpsons' (which I found disapointing), amongst other things.