Meh, the coop was only going to be released as DLC, so I don't feel cheated that it's not coming to the game after all. The game looks terrific, so I'm not going to let something trivial like this get in the way of my enjoyment. Not like I was planning on playing coop either, tbh.
It's not like it's a $60 game either. For $20 I feel the game already has tremendous value for money, even without MP.