A Realistic Review.
I myself never owned MW2, but I did play COD4. This game for me is a nice upgrade and new game types like kill-confirm I enjoy. Graphically it looks good to me, I mean how much do you pay attention to graphics anyways when you are in a PvP match. The character models look great, and they change to fit each map. There is a fair amount of variety in the maps. My one complaint is the size of many is a bit small with almost too much flow to them, you always have someone coming at your back it seems. Most are based in a village or city.
All the unlocks are a fun and the gameplay is fast and crazy as always. Yes you will see bunny hoppers and prone abusers, although they aren't much of a problem for me that often.
It is fairly quick to start up and get into a P2P match, where BF3 is a somewhat slow process.
I think the beef is so far they have poor support for dedicated servers, and I understand this. Also the lag issues with P2P. You will probably have to do port forward on your router, to help with the P2P at this point. It may or may not help to knock the lag down for the P2P games.
I think as time goes by they will get the dedicated servers going better and should be more of them. P2P is fine if you can get the lag down to bearable.
It is early in release I imagine there will be patches soon to help.
I never play the single player campaign so I can not comment on it.