My Personal experience:

-Elemental Shaman: 8. Despite multiple tweaks to my macros, multiple questions posted, etc, I STILL cannot get nearly as good of consistent DPS as some other folks on these boards. Though they can certainly still hold their own and are quite easy, just cant do best DPS possible.

-Survival Hunter: 7. Can do decent DPS, but not nearly as much as when I play him solo.

-Balance Druid: 3. F Moonkins!

-Ret Paladins: TBD. Just hit 80 with my team yesterday, I'll post once I get better gear.