Mages get a bloodlust/heroism ,and dont forget,we have cookies.Anyway,im not very sure about mage either.I feel that arcane is a pure pvp talent now ,and they seem to keep working on making frost pve viable ....anyway,the best pvp spec for a mage was frost,im not sure how we will handle in pvp at 85,if frost gets pve stuff,and arcane is a destro warlock without fear .Fire is like allways,decent at pve i guess,and bad at pvp...even if they keep trowing very helpfull pvp talents there,fire is like an arcane mage without that much burst...and arcane is just like a frost mage ,but without all that control...
So i think you should pick warlock.For them,the talent trees at least look clear