I'm glad it's finally out, I swore Activision would have had no choice but to do this much sooner.
I'm not sure if they fixed this but I don't think it's worth it for the MP, there's something slightly off about the aiming, not sure if it's netcode. It's just not as precise or in sync as CoD4 was to me. It might have something to do with the AW engine being retrofit into a 10 year old game. Campaign is bliss, though, I must have played it at least 5 times or so when it came out and got the platinum.