God of War, Uncharted, Gran Turismo and LBP are the system sellers (not so sure about LBP, but it seems likely). But there isn't a game that will make any of the big 3 win next-gen. To win, you need a combination of situations that will be favorable to you.
Actually, even Nintendo franchises can't solve everything. Gamecube proves that. A good price point, third-part support, some nice exclusives and extra features are the most important here.