One of the great 360 games. Its more modern and about a war with America vs a fictional Russian terrorist group.
Its basically if you mixed all the modern shooters and burned them, then took Halo 3 and made it have game sex with the whole call of duty series to make a awsome game baby that occurs inbetween the times of each game.
Also you get to stab people, which is always enjoyable.
Person 1: Hey wanna play halo 3?
Person 2: Nah I'm tired of being killed by 5 year olds, so ima play Call of Duty 4.
Person 1: So you wanna play with rednecks and middleaged men?
Person 2: Hells yes, so I can own them with my young people skillz!