Lots and lots of bitching in this thread.
I picked this up last night for 360 and have had a GREAT time so far. Coming from PC roots, I really don't expect a game like Call of Duty to deliver a mind-blowing, impressionable single-player experience (think Deus-Ex). However, from what I have played of the single-player, it's been great. Everything you would expect for a Call of Duty game. Tons of action, tons of shit flying through the skies, bullets everywhere, military lingo, guns, explosions, tanks, etc... The sensory overload and ability to blow shit up really shine in this one. I could care less about the story.
Moving on to the more important part of MW2, multiplayer. Holy Shit!!! I never really read about everything that was going to be included in MW2 multiplayer. Having been a huge fan of MW1's MP, I've gotta say that the MW2 MP is a huge leap forward. That addictive magic is back with the ability to level up and unlock all kinds of stuff. 22 pages of unique callsigns? Incredible! I love the customization this go around, it keeps it fresh.
I was realllllly worried about the balance in MW2's MP having heard about the ridiculous killstreaks, death streaks, dual weapon attachments, etc. After playing for about 2-3 hours last night online, my worries are dispelled. If anything, this game feels more balanced than CoD4. The absurdly cheap perks have been taken out of the game, the levels are quite a bit larger,and the radar seems to have been tweaked to give you a good idea of where shots are coming from without immediately exposing the locations of the enemy. Also, the game gives players control of some ridiculously powerful weapons; however, even though they seem over-powered, it's easy to avoid them if you play smart.
The multiplayer aspect just makes you feel individually badass while maintaining balance for everyone. That is a tough idea to capture. Bravo Infinity Ward, I'll be playing this for months to come.