I played an ironbreaker up to 20-I spec'd for offense and used a 2H, and did about as well damage wise as my swordmaster at that level in the closed beta. I like both classes, but the opening snare and absurdly favorable grudge mechanic are making me lean ironbreaker at release.
I played with my wife, who played a warrior priest to 20. Shit class, can't DPS or heal, and little utility. Runepriest or Archmage is way better IMO.