Best FPS for the 360, hands down.
Presentation:
The story is short and sweet. There are tons of pulse-pounding moments and intriguing plot lines. The HUD is nice and simple; and the menus are easy-to-navigate and stream-lined.
Graphics:
Some of the best around. So far on an HDTV, it bests Half-Life 2, Halo 3, Medal of Honor: Airborne, Rainbow Six: Vegas and The Darkness. I wouldn't say it would best BioShock or Mass Effect, by any means, but still. The facial expressions and animations are defined, the lighting is amazing and all the guns appear how they would in real-life. Even the landscaping and environments are finely detailed; bullet holes in the walls, dents in canisters.
Sound:
Decent score. All the weapons sound really great, as well. My only problem is that I highly doubt either the Middle Eastern Coalition or the Spetznaz prefer to speak English than their native tongue. The little breath hold and ringing of the ears from flashbangs are all nice touches.
Gameplay:
The controls for the game are just sharp, they feel dead on. The button layout also fits the the 360 controller well. The plentiful amount of weapons at your disposal appear balanced for the most part, however, (though this might sound like a "n00b" complaint) the snipers seem a tad weak and not as accurate as they should be. I have had it many times where I had all the time in the world to pick off some guy in multiplayer, only to have him slip away. I can't explain why it is possible that I pull the trigger 3 times to his head (while holding my breath), and not 1 of them hit the target. Ah well, besides that, I'm peachy.
Lasting Appeal:
Thanks to the short story, you'll be sent right into the frontlines of Xbox Live. Multiplayer alone is worth the sticker price you get Call of Duty for. Thank Infinity Ward for implementing Perks, a loadout screen, and a persistent ranking system; all backed by an awesome matchmaking service.
Basically, if you love shooters and online play, you should definitely give Call of Duty 4 a try. The modern era fits so nicely into Call of Duty's old theme of WW2, and it is just such a fresh experience (a feeling similar to that of Battlefield 2).