I don't do arena, too complicated, no time for that, don't care. Only BGs, so you can skip over all the annoying details of team composition and get into the partially stand alone completely random and anarchic area of BGs.
I got my warrior to 80 only recently. The gear sucks but it's usable, a few honor-reward items from BGs and a few PvE tanking items from doing the old heroics the tanking set.
Arms:
I've been trying this and I may be doing things wrong a lot. I get killed too fast mainly from overwhelming ranged DPS while attempting to kill someone in melee range. Ignore that, still get killed kind of fast when in 1v1 against a DPS class.
The DPS seems to be very dependent on a rend-overpower mechanic which forces you into Battle Stance. This makes arms very awkward in that it's designed for 2-hand weapons but the spell interrupt only works with a shield equipped. I don't want to be macroing stuff, it annoys me.
The other problem with arms seems to be the timer on charge. Some classes (hunters, mages, locks) now seem to have a number of break free / break away moves which outnumber 1 charge + 1 intercept on thei Arms spec cooldown.
I had expected Arms would be good against rogues but it seems they just stun me and I'm below 30% hp and dismantled by the time I break out of the stun. This is not very good.
Prot:
The DPS isn't great but survivability feels better it has a much easier feel overall. I can manage to survive longer, can actually kill healers due to the abundance of interrupts and stuns and the convenient fact that shield slam also has a purge-spam side effect. But when I'm in a BG people keep telling me to switch to another spec.
And I do better than arms even against rogues. Because I can stun them back and disarm them back so I can get even with the stuns and disarms. Actually I have found that rogues are impossible to kill with arms because even if you get a few lucky crits they just vanish/sprint/CC and escape but with Prot I can stun them when they are low so that I can kill them.
Fury:
From what I'm told it's totally broken and specially pointless for PvP. If things haven't changed it should be playable in Zerker stance allowing antiheals + interrupts + intercepts in the preferred stance.
Also I'm wondering what kind of effect is the succubus charm. I thought zerker rage would remove it but it doesn't.