i think they said it was the right bumper and what it does is make your melee attacks wackier (the various wrestling moves they showed in the E3 demo) it makes stealing cars awesome, and various other things
"Well i actually performed the experiment dozens of times. The bad news is reality doesnt exist. The good news is we have a new cat graveyard" -GLaDOS
Except if you haven't learned your lesson with Peter Molyneux by Fable III then you probably weren't paying attention to all the stuff he's said before, and how much he was enthused about wasn't on a level with his enthusiasm, or didn't make the final version of the game. The guy is just good at overhyping his stuff.
Civilized men are more discourteous than savages they can be impolite without having their skulls split. Official Phantom Stranger of the C&GN