This is the official trailer for patch 2.3: The Gods of Zul'Aman. The original description for the content featured in this patch is below. The full patch overview can be found here: http://battle.net/wow/game/patch-note...
The stronghold of Zul'Aman has stood for millennia as the Amani trolls' seat of power and bastion of the fearless, cunning warlord Zul'jin.
Zul'jin has spent several years plotting behind Zul'Aman's walls. Furious at the Horde for allowing his hated enemies, the blood elves, to join its ranks, he eagerly embraced a scheme that the witch doctor Malacrass recently proposed: to seal the power of the animal gods within the bodies of the Amani's strongest warriors.
Now Zul'Aman's army grows more powerful by the day, hungry to exact vengeance in the name of its fearless leader, Zul'jin.