Of course, the long awaited Halo 3. After all the hype and criticism, it's in front of you, pop it into the drive, hit play, and wait for the damn thing to load for a minute or two. Don't worry though, this is one of the best games you can get for the money, and it definitely lives up to the hype if you're talking re-playability.
The campaign is the one thing that irks most players, and the one thing that may drag down this game. An explorable, yet predictable storyline, coupled with the fact you have to go through it two or three times to get all the achievements on it, could be the most annoying things you will have to overcome in this game (although the reward is sweet enough). The campaign for Halo 3 is almost the same as the first Halo: Combat Evolved, way back in 2001, I think. You start out just shooting up Grunts, encounter the Flood about halfway through the game, and spend most of the last level driving to your ship before the world explodes. But of course this game is not supposed to thrive on the campaign. It's the multiplayer that really makes it shine.
Halo 3 Multiplayer is ranged across almost 20 maps (some are only available for download over XBL Marketplace), and a variety of gametypes. If you think you got enough of it from Halo 2, get out of your house, drive to Best Buy, buy this game, and hit yourself over the head with it until you get some sense, because this blows most multiplayer games away and will continue to have one of the best online modes for months to come. I myself have been playing online for 3 or 4 months now and it's pretty tough, but so addicting.
Overall, Halo 3 is a great game. If you don't have it, why the hell do you have a 360??