TBH, pallas are bye bye for tanking imho.
Blizzard have stated that Pala aoe tanking will still be the best, just that they want to avoid the situation of "LF Pala tank quick aoe run instance X". A modestly-kitted Warrior is one of my several level 70s and it's pretty upsetting to see how easily mobs peel off me to go for a healer when you've got 4 mob pulls and little/no cc. Palas just stand there and pap out a Consecrate and even a very bad Pala tank then won't lose aggro to a healer. Also, my guild's first Brutallus kill was with a Pala tank, so it's not like they can't tank the hardest hitting mob in the game.
Still, I can't see the new Thunderclap/Shockwave alone allowing me to go totally wild with AoE on my Mage. You currently can with a Pala tank so they'll retain a little bit of an advantage here.