Capped stats
It's better now, but GotEM and Celestial Focus (and talents of that ilk in all specs) still provide too much haste such that its realistic to get capped. Any class with so much vested in instant spells risks not valuing haste as much as other casters. That's okay to a point, but a big focus of Cataclysm is not to have these situations where players dismiss as junk gear that is targeted for them because one of "their" stats (meaning things like crit and haste for a healer, not hit or Agi) become excessively devalued relative to another stat. (Source)
Mandatory Glyphs/Talents
We're stuck in this trap sometimes where players want glyphs and talents to be meaningful but optional. That's a pretty narrow design space.
If we make a talent that affects Shield Wall, then it feels mandatory. If we make no talent that affects Shield Wall, then it feels like the talents aren't affecting things you actually care about and can become this potentially marginalized aspect of the game.
The argument seems to be that if you didn't have to get Improved Disciplines, that you could get some other potentially juicy talent. True. The same would be true if you didn't have to get Shockwave or if paladins didn't have to get Ardent Defender. You need Improved Disciplines, but they need Vindication. My point is that classes are balanced as part of their entire package. You aren't balanced at the core level with talents and glyphs thrown on as gravy on top of that.
Now we are making an attempt with Cataclysm to give players more options in how they talent. But still if you imagine a talent tree in which every single talent is optional, it's also hard to imagine how every single talent is interesting or powerful enough. (Source)
Druid (Forums / Talent Calculator)
Lack of new healing spells
Paladins are getting several new healing spells. Druids aren't, so I figured it was worth a little bit of explanation for why we made that decision. The short answer is that we're trying to find homes for all those druid spells that don't get much use. A devious alternative I suppose would be to cut Healing Touch and Regrowth and then make new druid spells to fill in the holes with different names. The druids that are going to be the most sad about the healing changes will be those who like just using the same couple of spells (Rejuv + WG in today's environment) over and over. I can't offer to much to placate them, except that unless you're up against the game's most challenging content, you have a lot more flexibility in how you choose to play your character.
Lifebloom is a good tank healing spell. Sorry if you find that delusional. (If you disagree with that, I assume it's because you put the paladin on the tank and the druid on the raid. That's a fine strategy, but we want to create more room for both classes to branch out.) Healing Touch is not, but that's for several reasons that we now have a chance to address: 1) Certain talents / glyphs / set bonus shore up spells like Rejuv a lot. 2) Healing Touch currently would overheal a lot. 3) Players would currently die while winding up a heal with such a long cast time. (Source)
Healing mechanics
We're not getting rid of the notion of druids using lots of hots when healing. We think that's an important part of the spec. There are some players who want to cast almost nothing but hots though, or some players who don't see anything wrong with the strategy of trying to keep Rejuv up on as many targets as possible whether or not they are taking damage. We want druids to make more *decisions* about which spells to cast and which target to heal. Some of you claim you do that today, and that's great. We want to reward you more for being good at that.
There are several heals that are just doing too much work individually in the current game, which makes other spells seem relatively pointless by comparison. Rejuv and Wild Growth are two of them, but so are Circle of Healing, Power Word: Shield, Holy Light, Flash of Light and others. It's not that the numbers are just borked on those spells (though they probably are in some cases). It's just that the current environment really rewards over-reliance on certain spells. We think the Cataclysm healing game will be more dynamic. There will be fights that emphasize efficiency and fights that emphasize triage and I'm sure there will still be fights that emphasize quick timing and spamming -- just hopefully not as many. (Source)