Warlocks are getting a new item designed specifically for off-hand use, known as "mage". With "mage" a warlock can eat mana biscuits, afk during wipes, blink targets into lavapits and gain spells once lost and given to other classes.
There are a few different types of "mages" a warlock can equip, depending on how many warriors he's kiting at any one time.
The "frost mage" off-hand for instance, roots Azeroth to the spot and allows the Warlock to roam freely, while everything else sits there, waiting to die from 45k iceshadow lancebolts. It also replaces the Voidwalker with a snowman.
The "fire mage" off-hand allows the Warlock to daze any target anywhere, regardless of range. It also allows the Warlock to launch a "medicine bomb" at the target, knocking it off it's feat indefinately. Only a full account reset can debuff this.
The third off-hand option "arcane mage" allows the Warlock to bend time itself, whilst at the same time flying through the air, nuking targets for 150k damage per shot.
The Warlock can always "cannabilize" the mage for instant mana and qq tears.
Finally, the Warlock gains a new power called "fuck you loladin" which automatically places a "Warrior" debuff on a Paladin. This debuff lasts for every bit of overhealing the Paladin does. The debuff lowers the Paladins intellect by 6000 and prevents any and all forms of action until the warrior is killed/ removed from the Paladin's back.
More news as Mists of Pandaria is unveiled!