User blog comment:Dolten/Call of Duty: Black Ops Achievements/Trophies (SPOILER ALERT)/@comment-174.71.3.159-20101001044016

I'm betting that Dead Ops Arcade is the other co-op mode that I've been speculating for some time now. I doubt Zombies are going to be the only real (Combat Training doesn't count) co-op mode in Black Ops.