Aug 30th 2009 11:23PM It isn't that haste can't be a regen stat and regen mana, it is that it won't be one for mages or warlocks.
The point of Haste is to allow the player to push more buttons. Rhe reason why increasing the regen rate for focus, rage, runic power, and energy will allow those classes to press more buttons is that generally their abilities have no cooldowns and are only limited by the GCD and how much energy/rage/focus/runic power is available (not so much for DKs). Thus, by giving them more rage/energy/focus, they can use attack more often.
If a mage was given more mana, they wouldn't press any more buttons than they normally do, they just might be able to press them longer. Additionally, if haste returned mana, there would be no need for spirit since healers use haste as well and if they could gain good enough returns on mana from haste then spirit would be as useless as it is now.
Aug 30th 2009 4:37PM Not really @ nyctef.
Healers will be able to pinch more often since according to Blizzard Re-Forging will never completely eliminate a stat, only reduce it by up to half and put those points into something else. All the stats a Mage currently uses a Healer uses except for Hit, while healers need Spirit instead.
So what we could be seeing is healers and DPS fighting over pieces that have neither spirit or hit-rating, while Hit-Rating goes to DPS and Spirit goes to Healers.
Aug 30th 2009 4:23PM Additional Note on Hit Rating:
Although not mentioned in the panels, I do remember in one of the Q&As someone ask if there would be an adjustment to Hit Rating talents so that all casters has a similar amount of hit rating from talents.
The reply was that they wanted to "do away with all Hit Rating in talents".
Now this could have been a primer to the Game System's panel with the Mastery system, or it could have meant that all hit rating is now meant to come from gear. Hard to say, as the comment was made prior to the Game System's panel.
Aug 30th 2009 4:15PM Haste will be staying the same for Mages, Warlocks, Boomkins, and every other caster.
It will be changing for Melee Classes, and Hunters.
Basically the point of Haste is to allow players "Press more buttons", according to Blizzard. Casters currently do this, while generally melee only have faster auto-attacks, which isn't "fun".
So now for other classes Haste will lower cooldowns and increase resource (Rage, Energy, and the new Focus) regeneration.