Played it for a bit on my laptop. Not bad I must say. Vast improvement upon MW3. I will say that some of the maps feel disorganised. I prefer my maps to be asymmetrical where one side of the map promotes a different style of play than the other side, and some of the maps feel like they got one portion and copy pasted it around the rest of the map so you end up with some sort of square pizza map with little variation. And for small clusterfuck maps I like them symmetrical (like Hijack).
I like the create a class and the guns feel ok, but it still feels like I'm shooting a toy. And the hitboxes are still god awful.
Haven't been able to get zombies working on my laptop, and haven't tried out the campaign.
Oh and the graphics are actually not that bad compared to the trailers. Really nice colours and lighting. Textures are nice on the guns, but still polygon as fuck.
For multiplayer I'd give it about 7.5/10.
For comparisons sake,
MW2: 8/10 (9/10 for aIW version)