I read somewhere it's like 8-10 hours, but I feel I'm near the end and yeah, it does seem short. I think it's just the effect of blasting through the game so quickly. I should have played the first run on heroic. I forgot to mention the couple of new vehicle experiences you get, which are awesome as well. I won't touch multiplayer until I beat the campaign, though. I want to get through it first, then get into PvP. I read about all the different game types, and they all sound great. I like the idea of free content with the spec ops releases, but I need to "free" up some memory so I can download them.