The MP is more fun than just about any FPS game I've played and that includes Halo 3, Halo Reach, Bad Company 2, Black Ops, Modern Warfare 1&2, Medal of Honor, and WaW. I would recommend it highly. The reviews are stupid for this game. They dinged it because they didn't like the graphics and the single-player campaign.
The single-player campaign is pretty decent-- I'd say it is similar in quality to a Bad Company 2s single player. Probably not quite as good as Black Ops single player.
Most anticipated games of 2011:
Uncharted 3,Legend of Zelda: Skyward Sword, Rocksmith
Modern Warfare 3, Super Mario 3D