Played Black Ops, I'm up to the Vietnam part on the campaign. So far My favourite level has to be the gulag part.
As for the multiplayer, I'm loving it. I've had a few lag issues, even a bit of freezing. However on the whole, it's vastly superior to MW2, Maps, customisation and weapons are great. I find it a lot less frustrating than MW2.
As for zombies, I've not played it yet. So far though I'm enjoying the game.