One of the best multiplayer experiences of all time.
Gameplay- The single player is pretty short, but its one of the most intense single player campaigns Ive played in a while. Its very chaotic, lets just say that. The multiplayer is the meat of the game. There are many modes, so many people playing, and very intense mode of play, and lots of weapon customization. You get weapon upgrades by getting headshots, kills with explosives, kill streaks etc. There are also many challenges that give you big XP boosts for things like shooting down helicopters with your guns, killing multiple enemies with one claymore, etc. The multiplayer is fast, intense, and awesome, period.
Graphics/Sound-The graphics are some of the best Ive seen on next gen systems. The shading is very well done, character models are smooth and realistic too. The sound is great as well. The guns have a great feel of realism in the sound.
Value/Fun-The single player is over quick, but the multiplayer will last you for a very long time. It is very addicting and easy to pick up, but difficult to master. If you want a fast paced shooter with tons of replayibility, Call of Duty 4 is the way to go.