If they make warlock a tanking class. I'm not kidding, this could work. If they completely redo the demo tree, itemize some cloth with +defence rating and stamina, warlock could be MT "drain-tank".
Using some skills and talent made for tanking like an equivalent to taunt, they could have their own tanking mecanism,relying on heavy health regen abilities and doind threath via draining.
A proprely geared warlock would be uncrittable/uncrusheable and have some nice sta, give some talent to compensate the lack of armor, maybe an improved Soul Link that gives like 30% reduced damage and redirect your pet's threat to you.
Any toughts ?