4x Warlock, 1x Priest is fun, but low.
The team has been a blast so far, and I envision them as a PvP team - mobile and nasty.
Still getting their toys and such, but they're already showing signs of their power.



I'm messing around with 5x Feral Druids.
Also for pvp.
Each is dual spec'd to Resto.
Might run heroics for gear, 1x Resto, 1x Bear, 3x Cat.
Or maybe just PvP for it.
At 5x 67th, took out (was attacked and killed) a 78th mage.
At 5x 69th, stealthed and killed a 5k gear score 80th warlock.
This team has a lot of power so far.



For PvE content, I'm using 1x Prot Pally, 1x Warlock, 3x Elemental Shaman.
Haven't really done a whole lot with them, but they've been good for everything I've tried.
They have heroics - Violet Hold, Gundrak, Drak'Tharon, and Utgarde Keep on farm.



A mixed team is different and fun.
I run Disc Priest, Arcane Mage, Feral/Boomkin dual-spec Druid, Elem Shaman, Elem. Shaman.
Pretty much just do dailies with the team, and am in the process of adding alchemy to most of my toons.



During RAF, I did 5x Disc Priests (Shadow to Mind Flay, a few pts in Holy, mostly Disc).
Surprisingly they were the fastest team to level.... 5x Smite killed anything level appropriate, in one volley; 5x Lightning Bolt did not drop most things and the 2nd 5x Lightning Bolt was a lot of wasted damage.
I'll be leveling them to 70th (from 60th) shortly, for trade skill purposes (want a 450 skill cap).



Similarly did 5x BM Hunters during RAF.
They're in a similar position to the priests.
I didn't like that pets seemed to run off and attack random targets.
But they were a deadly team during leveling.



I'm tempted to try the 1x DK (Frost/Blood) with 4x Ret Pallies.
It is a very popular melee team, and has had a lot of PvE and PvP success.
Haven't done this yet.