Bit of a let down, in my opinion.
Campaign started strong, but weakened very quickly. There are some fantastic missions, but they're all right at the beginning. The ending is unsatisfying for me (for the sake of not spoiling anything, I won't say more, but yes, I tried everything).
The last few missions feel rushed and lack substance, urgency or interest.
Zombies is pretty fun, probably the best part of this game.
Multiplayer... I'm not impressed. Aim assist is broken, the small amount of maps is a bit naff, and there are some that are pretty poorly designed.