fail fail fail fail!!! Don't know anything about rogues, but i do warlocks xD
Depending on your intellect, either go DEEP affliction(if int is low) or DEEP demonology(if int is high) for Leveling and pvp. U burn mana alot when demonology, but do decent dot damage(curse+corruption, due to insane spell damage) and high shadow damage with SB. And as affliction u do INSANE dot damage, and if u know how to play, will never run out of mana due to life tap etc, and ur health will always stay 100% if u have better than green gear due to life siphon(and drian life is AoEing). And thats another story, AoEing. Using demon form when demonology does ridculous-stupid infact- damage to everything around you, so its good for pvp coz melee get ummed hitting u, and they hit u for nothing due to the increased armour and stuff. Also u have ur felguard/voidwalker to aggro several 100 of mobs in pve land, and then u just charge in with aura and then use rain fire, killing everything(it really doesnt matter how many mobs, lvl 72s hit u for like 10)...but u will run out of mana if fight is long.
On the other hand, dot, run, dot , run, dot, run, dot, run...maybe fear can kill anything and everything just takes slightly longer due to dotting each target individually. But u wont die(due to life siphon) and wont run out of mana, due to life tap and the pet mana tap thingy.!!!
And thats it, i recommened demonolgy tbh for best of both worlds and just carry some water around with you
Hope that helps