I was playing MW2 online and i m hugly disappointed.I only played a bit of online from MW1 and WOW and for this one i got upto level 10 .
let me start:
first of all the maps are too big for 10 -12 people.
graphics online is like a polished PS2 game(SP is beautiful but online ,,,ughhh)everything is low res it's like rainbow six vegas graphics .
the minute you step out your dead from an unkown place.
it's very fast paced like UT3/R2.
Class based multiplayer with different ability is much much more fun.
the only positive is that the aiming system is extremly forgiving of your error while shooting.
I honestly don't see why this is popular at all.
KZ2 is much more epic and hectic with 32 players in the room.with 10 turret bots,8 air support,etc...
I give MW2 online a 6.5 and a 9 to KZ2 online.
people that are even comparing the graphics of MW2 and KZ2 either are joking or haven't experienced KZ2 online.