Check out Gamespot or IGN to find out the differences. The Xbox version is going to be improved, believe it or not. It is supposed to look as good as the PC version (read: not watered down port). It has a, Quick Action mode I believe its called, where you fight off hordes of enemies without an objective (think Mercenaries from Resident Evil 4). I think they have more missions too, like cutting room floor stuff.
