Actualy, in active players, we have :
A Heal Priest
A Tank Warrior
A Warlock
A Paladin (dont know if he is holy or tank or ret).
You can play what you like, Holy paladin is nice too (we should need all for raids 10-25-40). Until we reach 60 i think we would recruit some other class so mage, rogue, hunter, drood are all nice ...