I guess they figure you're up to speed by playing MW1 and 2.
Half the time, I don't even know what weapons I'm carrying. And I don't really care for the lack of continuity, hop-scotching from a submarine to a russian airplane, to some little shithole in Somalia.
It is pretty slick, though. Once I get used to this, I'll probably tone it down to LA Noire or something where I can follow the plot. This kinda freaked me out a little, in the beginning. I was afraid I'd jumped into the deep end of the pool, and wouldn't be able to make it past the first board.
LOL, I shot a chicken.