Part of the problem is that MW2 caters more than ever before to noobs, and pricks take advantage of this: People pick up strategies which give them easy kills and make it horribly unfair for people playing properly.
(for example one man army + noob tubes; overly accurate shotuns; marathon + lightweight + tac-knife, thermal scopes, painkiller, to name but a few)
Now fair enough they CAN be useful, but when i see a guy spend the entire game knifing people and running over my claymores unscathed it makes me sad inside and i feel the series has lost a little something.
Also, it doesn't help that infinity ward seemed to ignore it's fanbase after the
game's launch: The number of balance issues with MW2 which didn't get fixed are staggering (yes im looking at you UMP with your silencer which raises accuracy but glitchily doesn't lower bullet dammage).
It's like they took our money and then abandoned us to a harsh landscape of the prickish and the unskilled looking to pray on people behind cover with thier infinite noob tubes or camp us out from behind a corner with their heartbeat sensors.
Also, the fact that throughout the game's life nothing has been done about any of the hackers: 10th prestige lobbies have been running freely sice day 1 and modded controllers are more common than ever (If i get killed again by a FAL firing like an LMG I may just scream...)
Surely...surely there must have been something you could have done by now if you could be arsed!
The game is a damn magnet for cheaters and fools looking for easy kills, and it's runing it for people who want to play the game skillfully.
For me, if Blackops doesn't get it right I may lose faith in these games forever.
Rant over