He's already got it, but that was awful generous of you. You should take the extra copy up to Game Stop, EB, or whatever you have in your area and get some credit towards another game.
So what are you playing? I've really enjoyed BioShock, Mass Effect (!!!), Oblivion, and the RTS Lord of the Rings game, though it's name escapes me at the moment. (Too much of the ganja.)
A 360 is way out of my price range, so I live vicariously through my brother.