Warlocks....  

Warlock are really over powered cuz they have so much spells that do really good DMG with curses etc. With Pets ... Really Overpowered... But rogue's can kill them easily

I used to play a warlock, back then when I was still playing WoW.
WoW had a balance problem in the beggining, but I tought they did
some change and nerf warlock a few time (along with the rogues) no?

warlocks are awlsome and yes they are overpowered too many spells and good DMG

I guess I'd have to say they are. I get killed by a lot of warlocks in pvp. Those dots are killers. Death coil is definitely anoying. lol But I don't think that a game that is mainly a pve game should be changed so much because of pvp. I know a lot of people play it just for the pvp, but come on. Pve suffers because pvp'ers are complaining. And rightly so; some classes do seem very overpowered against others.

PvP in World of Warcraft is just a fancy game of rock paper scissors. Warlocks may seem to be overpowered to some classes (casters mainly) and an easy kill for others (warriors and rogues). With Resilience reducing the damage from their DoTs, they can no longer be considered over powered... unless you don't have any Resilience, then you're out of luck.