It's really complicated to please gamers these days.
Modern Warfare 3 is still the CoD Modern Warfare game many of us loved. I don't really get why people are getting disappointed just because MW3 stuck itself from its award winning roots.
Personal Rating of Game Modes in MW3:
Campaign - 10 (simply exhilarating)
Multiplayer - 8 (not a fan of the new maps, but gaming experience still rocks)
Spec Ops - 9 (Always a great variety when I get tired of the usual multiplayer)
It's really getting hard for game developers to please gamers these days. When games like Final Fantasy experimented and almost completely altered the gameplay from its predecessors (Yes, FFXIII), people bashed it.
Now, games like MW3, who just stuck to its roots gets bashed as well. I don't know about you guys but it's still a great game for me so I'm giving it a 9.
Get it and see you in the multiplayer arena. :)