cata prep - resto sham or tree

[Khatovar]

IIRC Replenishment doesn't stack, the newer one will overwrite the older one.

Shamans do have some "can't stop, mobs will eat me" mojo going on with Earth Shield, Riptide, Healing Stream, Nature's Swiftness when needed, and eventually Spiritwalker's Grace and Unleash Elements. And while not instant cast, Healing Surge is a really nice heal with a low cast time.

But, that's just my opinion playing with a shammy, I'm sure someone else can come along and give some pro-druid rebuttal.

[Noids]

Currently playing with resto druid for my shammy team and resto shammy for my pally team.

Both of them have nice utility and reasonable mobility compared to the other healers. I chose the druid for the shams because having a tank is nice for PvE stuff and I love instant roots for immobilising ranged targets to nuke.

I like the shammy for the melee team, because chain heal is great on the bunched melee and frost shock is a great snare for the pallys. The sham also brings the haste totem for the melee, which is the best melee dps buff that a healer can bring I guess.

If you are running a mixed group, why don't you consider a holy priest? Can't beat these guys for easy multibox group healing IMO with circle of healing, prayer of healing, prayer of mending and spammable HoT.