30. Call of Duty: Modern Warfare - 360
I often consider this game to be the best FPS of all time, and it is in many respects. It has a fantastic, exciting campaign with some very characters. The gameplay is exetremely smooth and works very well. I don't really have any negative things to really say about it. I put several days into the multiplayer. The experience system was the perfect motivator for "Just one more game".