Call of Duty 4 and BioShock are the two best FPS of this generation, in my opinion.
BioShock: Incredible single player experience with a great story, many ways to approach everything, reasonably open-ended. No multiplayer.
Call of Duty 4: Good enough campaign, but the multiplayer is one of the best for a console FPS ever. If he's into online gaming, he'll get months of play out of this.
There's also Halo 3, but I would say those two are better.







