I played Modern Warfare 3 a few days ago.
I really wanted to play and enjoy it, but unfortunately that was not the case.
I don't want to go on a rant about how bad it was, because it was not horrible, but frankly I did not enjoy it. All the predictions about how it would be exactly like Modern Warfare 2 were true. Of course, I did not get hit by a noobtube even once, but the guns for the most part were overpowered.
It played very similarly to MW2, yet I had less fun than I did with Modern Warfare 2.
It just seemed plain and uninteresting to me, even the survival wasn't very fun or exciting.
I played the campaign as well, which was nowhere near the epicness of MW1 or 2. It just kind of bored me. At least we killed Makarov!
Unlike Modern Warfare 2, the Spec Ops missions were pretty much EXACTLY like a part of the campaign, where in MW2 the specs op missions were mostly a lot different than the campaign missions.
I just don't see how anyone would have fun with this game for more than a few hours even if they are a CoD fanboy.