WOTLK tanking pets?

[Hishumaa]

Does anyone know which pets are good for holding aggro in a group of enemies?

[Qiana]

Any tenacity pet can hold aggro in a group. Best is a Turtle for tanking cause of its survival ability.
Btw tenacity pets are bear, turtle, worm (exotic), gorilla, crab, boar, crocolisk. All of them have ability to hold aggro in a group of enemies.

[DarkenedHue]

A bear will hold the best AoE threat due to having Swipe on top of Thunderstomp.

That said, Pet AoE threat in general is pretty pathetic, so your pet is going to be direly reliant on you for your MDs.