What are the best online ps3 games out there?

If i were to buy a ps3 ( i will) what games should i get that allow online play? I like online play as i can play with friends, and not just bots. I like shooters, rpg, racing, sports, anything basically that generally doesnt suck.What are the best online ps3 games out there?
Call of Duty 4: Modern Warfare

Call of Duty: World at War ( its not as good as CoD4 )

KillZone 2

MotorStorm Pacific........

LittleBigPlanet

Metal Gear Solid 4

Any Sports Game is Great online

Resistance 2 (after you play Resistance: Fall of Man)

Massive Action Game (M.A.G) ( its coming soon, 250 people on ONE map, its gunna be AWESOME)

basically any game on the PS3 that is playable online will be great as long as you like that type of gameWhat are the best online ps3 games out there?
Call of Duty 4 and Call of Duty World at War are really good online games. I find them quite addicting. If you're looking for a challenge then Warhawk is a great multiplayer game that has a steep learning curve but it feels rewarding when you get up the ranks. LittleBigPlanet is a cute game that casuals and even hardcore gamers like myself seem to be drawn to. My only complaint about LBP is that there are lag issues. Anyways, there are a lot of good online games for the PS3.What are the best online ps3 games out there?
well i will give you the best games by categories

First person shooter top 3

Call of Duty World at War

Rainbow Six Vegas 2

Call of Duty 4 Modern Warfare

none first person shooter

Grand Theft Auto 4

Street Fighter 4

Metal Gear Solid 4

racing

Motorstorm Pacific rift

Sports

any one made by ea sports or 2k sports

rpg

no rpg has online
KZ2, call of duty 4, Little big planet, and grand theft auto 4 is pretty good