Here are some quarrels I had with Modern Warfare 2's multiplayer:
- Respawning gives you a sense of disorientation for a few seconds. When Blade-Runners are running around, it is common for me to spawn then get shanked immediately after, wasting another 4 seconds.
- Camping. The maps actually encourage you to do this. One example is in Skidrow in Domination. There's a spot in the second story of the building (just above "A") that has a small opening in the wall, perfect for shooting opponents who might try to capture the point. All you need is a claymore or two, and you'll be fine for the entire game (so long as you replace them, obviously).
- Noob Tubes. While they can be used expertly (what with the arcing of the projectile to hit unseen targets) you'll find that players tend to use them as a primary weapon instead of using it as an accessory for shots that require a parabolic arc. Thus whenever they see another player, they launch the grenade roughly at their opponent's feet, killing them instantly.
- Blade-Running (when I say this, I mean Marathon-Lightweight-Commando). There is actually some skill in it on the bigger maps, but on the smaller maps it completely rapes the opposition. I realise it can be countered with a simple shotgun, but often the knifers will come out of nowhere, giving you no time to react.
- Killstreaks. The less noticeable ones are fine (UAVs, sentries, etc) but once you get on to the deadlier ones, it's almost impossible to take them out (looking at you, AC-130). Even if you use Cold-Blooded, you'll often spawn next to someone who didn't, and get blown to smithereens by anyone who can spam left-click (granted, s/he had to get 11 kills to do so, but that's beside the point). And whoever thought of a Tactical Nuke should be shot in the foot. Yes, it allows the better players to shine, but in TEAM Deathmatch, this should not be the case.
Nor should it be allowed in Domination. One time my team was clearly winning, we had all bases covered, but some Tuber had managed to rack up 25 kills and one the match for his/her team, despite not having captured any bases (I know this since I checked his stats- he had exactly 25 kills and the same number of points to do so, without any bonuses whatsoever). Glitching makes it even worse, since 4 kills are needed to end the match.
- And finally, the lack of dedicated servers / map-editor. Infinity Ward was (somewhat) clever by using this ploy: since players couldn't use player-made maps on IW.net, Infinity Ward could charge whatever they wanted for maps that (in all honesty) would have been free, for example the old CoD4 maps released in the Stimulus packages. I almost spat out some of the water I was drinking when I read that Infinity Ward would be charging FIFTEEN dollars for FIVE maps, TWO of which were from CoD4.
Though it didn't make me nearly as angry as when I found out a lot of my friends bought it, effectively encouraging Infinity Ward to make a second overpriced map package.
The lack of dedicated servers in general pisses me off to no end as well. It takes about ten minutes to actually get into a game, and usually the host lives somewhere far from everyone else, so s/he has four green bars while the rest of us have one red one. Furthermore, you can't actually kick anyone who's cheating or being a general dick. You can't actually remove someone who's using Auto-Aim (which is fairly obvious to spot) and Infinity Ward took their sweet time in patching some of the glitches (some of which still aren't fixed). So much for those "hack-proof" servers of yours, guys.
tl;dr : Infinity Ward are a bunch of money grubbing dicks.