The biggest thing that I see is that they're trying to make mana efficiency important. I expect they want to see it where burst = expensive, slow/steady = efficient. It's logical, but it raises some significant discussion, namely rage/rune/energy vs. mana.

Currently, mana is the only one you can really run out of. The others, you either wait a second or cut back your attack, and then you can dive back in. Theoretically, this can go on forever. Mana, though, after all the potions, skills, whatever... you're done until combat is over.

Speaking as a healer, there are a lot of fights that COULD be won, except we run out of mana. When that happens, we're a target dummy. We sit there, popping tiny heals every 5 seconds as we get mana back.

It would be great if they'd address this, either with the implementation of something like "exhaustion" for melee (the longer they fight, the weaker they get, with bursting speeding the process), or an increasing return on mana while not casting. It'd level it out to where efficiency is important, but it's also important to coordinate so that healers can trade off and/or tanks can drop into full defensive while the healer rests.

As a shammy healer (with effectively NO instant heals or HoTs and an inefficient mana pool - thanks again, Blizz, for the change in potion mechanics that prevents me using more than one pot in the course of any boss fight...) this ought to make life just a little bit more difficult.

It does seem sometimes that Blizz is still stuck in the "the only thing a shammy healer is good for is chain heal in raids" mentality, and doesn't bother to consider us when talking heals. My sham has been resto since her first talent point - has suffered through leveling in one of the game's least-capable solo builds, dealing with the attitudes of people who think that a resto sham can't party heal - and more than anything, dealing with changes designed around the idea that only priests (and sometimes druids) heal.

Ah well - I am not normally a whiny sort, but must admit I am among the crew who consider many of the changes described as coming in Cataclsym as "******** up/destroying Azeroth" so perhaps I will just join the QQ crowd around here and mark it up to a concerted effort on Blizz's part to phase WoW out in favor of their new MMO. In both cases - I certainly hope the implementation is better than the description makes it sound.

LOL, right off..
They need to redefine base health for a pallies Lay on Hands.
This just messes up a slightly broken concept.

Bubble and lay on hands are apparently the hallmark that they seem to think defines pallies, rather than healing melee class.
Full heals may be a bit broken if there is tons more life.
It may also be more fun until they fix it to run around in BGs annoy the living daylights out of the people who have always QQed about pally stuns, bubbles and LoH :D ...that and the ever present DKs who don't know they made a mistake gripping the person who will kill them :D

Hoepfully this will mean a new generation or two of healing potions. We seem overdue as it is.