So, I rolled a monk. As I'm the optional 3rd healer in my raid, and because Disc has some problems, I leveled a Mistweaver. Unlike some well-prepared people, I leveled it all the way from level 1, without any instant recruit-a-friend levels. But that's not what this post is about; the actual healing at level 90 is. First, I'll start with things important to non-Mistweavers.
Healing Spheres
The little green balls everywhere? Those are healing spheres. They can be manually cast, or proc off of any heal. They heal 25-35k or so if an injured player touches them. There's no cooldown on touching your monk's balls, so if there's a bunch of them, you can heal tons of health all at once by walking through them. Think of them as a second Healthstone. Tanks, particularly, can make use of these to great effect by tanking near a few, and sidestepping into them if things get rough. (Everyone can do that, it's just most awesome when tanks do it.) When most of my Healing Spheres get used, they're about 20% of my total healing, so if you're grouped with a Mistweaver, do pay attention to them, particularly if you're moving anyway, or the healer is struggling.