WoW Hotfix - General Vezax
It looks like everyone's favorite mana encounter just got that much harder, and at the same time, much easier. Druids and Shamen will no longer get the benefit of their free casting abilitiies or activated mana regen, so they have to suffer like every other mana based class and enjoy the vapors. The good news is his health has been lowered drastically to compensate, but he also casts more often. So less health, less mana, more casting. Overall it sounds to me like the encounter was made a little easier to assist with the transition from Ulduar to the new raid of 3.2, but we'll have to see how that casting change mixes him up!
You can find the full post here for the exact details of what changed and more.