Thought I would share some of my thoughts on what I've seen so far for cata raid healing.
First of all, mana matters, but not as much as I thought it would. the bulk of my healing is still Chain Heal. And encounters are looking to be decently tuned to the healers mana. So there is waves of aoe, followed by single target spike. repeat. The name of the game though is efficiency for sure. In every raid I've done (3) my average overheal was in the area of 10%. So healing smart is nessesity.
On the above topic, there is a downright OP trinket, which I will prob make mandatory for all healers to buy with their points first. Pop it and your spirit goes up by lil under 2k for 20 seconds. (basically doubling your spirit about for first tier gear) Why such a big deal you ask? Because Mana tide increases your spirit by 350% and it stacks with the trinket.. It works out to in a raid setting basically regenning your entire mana bar. It's a must have.
non healers actions matter a LOT more. And by this, I mean that a lot of the encounters have a ton of avoidable damage and mechanics that require people to be smart. The days of us healing through everything because we can are over I'm afraid. There is a LOT less leeway for errors.
Tanks still can get gibbed. Not 1shot that I've seen, but you bet your ass that if you stop healing for a couple seconds you could lose a tank. However it's more of a tank get hit for 20-30k, then every once in a while, just get destroyed for a few seconds, then back to normal hits type thing. Not the constant SMASH SMASH SMASH like what you see in wrath. Still, this is only first tier content, and with gearing, who knows... But regardless this means tank-healer communication is essential. CD's are going to become staples and well need effective ways to communicate the need for them.
Trash is actually hard. It's odd but making detailed pull plans for trash packs is amusing. Hits pretty dam hard too.
Thats about it for now. If any questions feel free to ask.
