I know that warlocks are said to be overpowered in PvP, which I have no personal opinion about – I never PvP’d on Ravven, only on my hunter. The cast time of fear, etc., meant that I felt too ineffectual; I hated standing there for several seconds trying to cast something with rogues stunlocking me or otherwise smacking my squishy cloth ass. I do think that it is a shame that classes now are balanced for arena play – most players don’t put any serious time and effort into arena. I used to love AV, as it felt like a real, manic battle – arena feels too much like duelling which I have always absolutely refused to do.
Part of that may have to do with always having been a Destruction lock. During the 60-70 levelling period, I did spec Demonology with everyone else, but I didn’t try PvP. It was a good levelling build. Destruction suits my playstyle, and is good for raiding…it’s a tough build for grinding, farming, and PvP, though. Hence the fact that I’m only on Ravven for raids.
Are warlocks overpowered? Not for raiding. Not for farming. For PvP? Perhaps, according to a lot of people. The character that I personally would love to see nerfed for PvP are rogues. Man, I have some major rogue hate from my WSG/AB/AV days…I HATE those guys. :)