I need advice on multiplayer games to play

I played Team Fortress 2 for a good 3 days, but I don't like it. I forced myself into enjoying it and stuff, but now I officially gave up with it.

I got it for free after installing Steam, I thought I'd have tons of fun.. so now I'm hunting for some other good multiplayer games to try out that are not mmorpg's.

any advice?

Quake Live. It's free and better than most games.

by my opinion,if someone plays it anymore - Tactical Ops:Assault on Terror

- Diablo2

- Counterstrike Source

- Red Orchestra2

- Starcraft2

- Brink

- BC2

- Dead Island if you want coop

alien swarm (free through steam)

half life 2: deathmatch (free through steam if you are gaming on a DESKTOP (any arent using an intel gpu))

starcraft II as someone pointed out

counter strike: source

battlefield: bad company 2

guildwars + expansions

magicka

left 4 dead 2