Okay so I'll be making a new thread when AW comes out. I have an updated list as far as best to worst CoDs in my opinion.
Bo2, Mw, Mw2, Mw3, WaW, Blops, Ghosts.
The reason Ghosts is at the back is just purely how many problems there are and have been with the game. In general, there is a HUGE internet disadvantage. What I mean by that is if you have bad internet (5mbps down or so) and someone else has good internet (50mbps down or so), and you get in a gunfight, the person with the better internet will 1. Have better hit detection with their bullets, and 2. See you before you see them. This gives them an extreme advantage and you can almost never beat them in a fair gunfight. There's also the fact that there are a bunch of glitches in the game, such as the SnD bomb glitch. This glitch came about a few months ago, and basically it didn't allow you to plant or defuse the bomb sometimes. They patched this glitch, but a few weeks later they came out with a new update to bring new camos into the game, and that update brought the bomb glitch back into the game. I don't see how you can fix a glitch, and then come out with a new update that brings the glitch back. There are also a LOT of instances where sniper bullets do not hit the person, even though it's very clearly aimed at the character's chest. You can also sometimes not kill a person when hitting them in the head with a sniper bullet. As in you get a hit marker, but no kill.
I think the game will die out very quickly if AW is not good. From what I've seen, and from what I've heard from pro players that have played the game, it looks really fun, balanced, and is going to bring a whole new feel to CoD. I have very high hopes.