Warlock or Priest? World of Warcraft?

I have a warlock I used to level... but I kinda got bored of him after Cataclysm.If it were before Cataclysm, then a warlock would work great.However, Cataclysm made warlocks underpowered, while mages became even more overpowered then before.So don't bother with a warlock.I'd go with a priest, but I don't know much about them (mine is still below level 20), so they may bore you.