I voted 'other', where i vote for eve-online.
I played e-o, wow, l2, gw, mu, tibia, and many more.
Why do i think that e-o is best?
It's advancement:
Eve is most tech advanced game. I never taken part in a 500vs500 fight in any other game.
Game client runs smovely. When i comape it with wow, or -oh noes- l2, it is pure leetness. In wow or -oh noes- l2 you go to city where is lotta people, frame rate will drop a lot [i have c2d e8400, gf8800gt and i run crysis smothely, so it's not 'bout my config].
Also, it's content advancement. Eve is most advanced game when it comes to content i believe. After playing this game for a year now i still don't know [ i haven't done by my self] a lot of stuff.
Community- we do have spammers, lolpeople and stuff, but... it's better. Eve is more realistic- we have politics and stuff. just take a look at wars. Wars between aliances aren't 'oh, let's wardec them for this evening cause i'm borded'. they take months and it is about staying alive or packing up your assets.
What i don't like about eve? Changes... changes that have came to eve recently killed -are killing- solo pvp. pvp these days is about who got bigger blob.
Also, game worth of skills got nerfed. Game is being pushed towards newbies, not towards people that lent this game exist when it was needed.
Another thing... game is pushed towards highsec [something like no-pvp place]. Plenty of people never left highsec, which makes me very, very sad panda. This is a problem, cause sometime ago, you could've actualy go to highsec and killsomeone [after what you wuold have to fight guards]. Now, you can kill only smallest of ships, which preety much suck, cause carebears feel to safe.
This is my vote for EVE-Online.
2nd would be Lineage 2 for it's fast pvp.