I'm not gonna be a douche and say it's going to be a bad game, because, shit, i was ready to hate MW, and that game ate up god knows how many hours of my time. I'm not a big fan of "realistic" gun porn for various reasons; Borderlands' brand of crazy bullshit is more my kind of videogame tea. But still. MW played mad tight, had a mostly interesting campaign with great, memorable moments, and i'm sure MW2 will do its best to outdo its predecessor.
 
But man, that online play.. 
 
It's awesome. Maybe too awesome? MW became one of those games, like R6 Vegas or Gears, where if you didn't spend every waking moment playing, the community simply ran off. The R6 community became so abrasively idiosyncratic it became absolutely impossible to get into a game without being kicked for breaking some unwritten rule, or simply because you didn't have a high enough rank. That's right; You were routinely banned for not having played enough. On the Gears tip, that game just became chock full of god damn specialists who would pop your head off with sniper rifle hip shots. It just made the game less fun to play. 
 
MW didn't sink that far, but trying to get into a MW game today after a good while of not playing it is absolutely impossible to enjoy yourself. The community is simply too damn hard core, and too damn good, and in most cases, very happy to tell you just how bad you are at the game.
 
So i have this feeling, with MW2, there won't even be that lull post release full of inexperienced players. I'm pretty sure a lot of MW2-players will be returning MW players, and god knows they are prepared.  I don't know of a solution for this thing. On the 360, Trueskill has been a less than successful method of matchmaking over time, simply because the overall skill level is so high. I suppose today's "fix" for this problem is to throw in a coop survival mode, but, my god do i hate survival modes.
 
The result is, i'm not sure there's going to be any multiplayer for me to get into, and to be honest, with IW's style of super-scripted campaigns (MW in particular had notorious bits of Endlessly Respawning Russians where the only way to beat the enemy was to.. Charge ahead until the respawn stopped?), i'm expecting to see huge heaps of MW2 on the resale market. Which is honestly where i'll probably pick up my copy.
 
I hope this doesn't read too much like bitching about the game itself. The "problem" is that they've simply made too good and too popular an online shooter.
Or maybe i'm just being completely wrong: God knows i feared this with Halo 3 as well, and i had some fantastic times with that game. Hmm. We'll see.