WARNING: These numbers are based upon DPS simulators for CATA -- probably not completely accurate lol
So, basically, you might be in a situation trying to figure out what class you want to pick that will do well in Cata. Well, remember how Blizz always keeps saying that at 85 it is all balanced out? Well, these numbers are based on your character being in BiS gear and it is assumed they perform a perfect rotation.
READY?
1.Shaman (elemental) - 24868dps
2.Warrior (arms) - 24810dps
3.Spriest - 24223dps
4.Warlock (aff) - 23927dps
5.DK (unholy) - 23674dps
6.Druid (balance) - 23322dps
7.Mage (fire) - 23164dps
8.Warlock (destro) - 23120dps
9.Warlock (demo) - 22554dps
10.Shaman (enhancement) - 21577dps
11.DK (frost) - 20803dps
12.Warrior (Fury) - 20770dps
13.Druid (Feral) - 19703dps
14.Mage (arcane) - 18856dps
15.Mage (frost) - 18783dps
16.Ret - 17892dps
17.Rogue ( mutilate) 17649dps
18.Rogue (combat) - 16885dps
19.Rogue (sub) - 14565dps
20. And Hunters... - N/A dps (Yup they are pretty bad in their BiS tier gear still lol)
LOL enjoy your decision making (REMINDER: These numbers are not reflections of ACTUAL dps, just reflections of what your dps on your gear says you can do based upon a dps simulator. lol)