What I hate:
Sad acts constantly camping.
Incredible Bullet Damage.
SCAR H (The New MP40)
People who steal Care packages.
Grenade Launchers being unlocked so early.
People like CodeMajic who HAD to get the game before everyone else and hack his sad life to the top. (Thought IW said they where going to reset leaderboards a day before realease..)
Pain killer.
"Finding best host" In lobby isnt as good as made out; The game starts. Check your connection - everyone has one bar. Look for the host, his clan tag is [ESP] A Spanish host.. is the best? Think again IW.
Still poor respawns.
The 'Noob' Friendly Delays. Such as: Someone spawns behind you, and shoots. In CoD4, 5 you could run to the side or dive in cover just before you die. In MW2 you stand not even the slightest chance. Before you know it, kill cams up and your being sprayed by a SCAR or an RPD.
Apart from that I love the game!