I can't see noob tubers as being a problem on any platform. I mean, in MW3 pretty much you need a direct hit to score a kill. In MW2 there was a perk to make explosions more powerful, in MW3 instead there is a perk to lower damage you take. Also in MW2 you could replenish with One Man Army or Scavenger, giving you an infinite supply to spam with. Much easier to just shoot a guy in MW3.
There are still things about the multi that bug me. Spawns, hit detection, lag (noticeably worse than MW2 in those areas). The maps still kind of suck, but I've warmed to some of them. Downturn is probably the worst map in any COD game ever though. The biggest problem with the map design is that there are just way too many places to 'head glitch'. Why the hell do you put so much neck high cover into a game that doesn't handle it well at all?
Best weapons I think are the Type 95 for ARs, with an honorable mention to the ACR 6.8, and for the SMGs I like the MP7 with honorable mentions to the UMP45 and the one that looks like a super soaker (but really it's just a not as good MP7 that unlocks way earlier).
Another thing that drives me nuts is the sheer number of challenges I always seem to be finishing. I'm trying to soundwhore people with sitrep pro... but check out how much that stupid screamy noise plus guitar riff plays in this clip. (Ok, and I'm using this as a test case for the YouTube integration in COD Elite):
[yt]http://www.youtube.com/watch?feature=player_embedded&v=kfbPdq5UQ6s[/yt]
I would really love to be able to turn that damned sound off.