WHM looks to be getting some buffs, but I have to agree with Nihility, there is only one safe and secure healer in my mind and that'd be SCH.
- Supervirus, which has ranged from just regular Virus to the only thing standing between the group and death due to iLVL? Check
- Can DPS while directing very generous, unhampered heals at the boss's target? Check
- Can AoE better than half the cast of jobs by spending 7.5s and one Aetherflow to set it up for the next 20s? Check
- Adlo for general mitigation, and the ability to virtually negate the next tank killer if it crits? Check
- Selene massively boosting raid DPS for free? Check. We've dabbled in dropping SCH for solo healing in the past and it rarely pays off well, SCH DPS + Selene buffs are damn near a DPS by itself. Technically even stronger in 3.0 due to SS buffs
- If needed, completely free, strong raid heals/buffs from Eos? Check. It's hard to notice how good Whispering Dawn really is until you try solo heal SCH and realize WD usually heals the whole raid almost to full by itself, usually well before next mechanics (situational).
- 2 minute CD on Eye for an Eye, check. Anyone who actively uses this knows it's actually a big deal, and WHM/BLM have a high 3m CD on it. AST won't even get it.
- Lustrate, which oddly enough isn't even one of SCH's best strengths. I've seen it countless times, a DPS screws up a mechanic and is brought near death before another mechanic, a tank fails the CD and is left with pixels of life, the other healer is slacking ... Lustrate to the rescue.
- Possibility in 3.0 to crit Adlo the raid before a T9 Megaflare/T13 Gigaflare type of attack? Check check check
I do not know which healer will prove dominant of WHM or AST. Probably will lead to personal preference mostly, maybe WHM for progression, maybe AST for speed runs since presumably higher group DPS, who knows? But I know SCH isn't going anywhere. 2 stronk.