Bah, scratch that, I never had space for Glyph of Rebirth before 4.0.1 and I just realized it brings you back at full health, but it doesn't say full mana....

Except for how, then a healer dies a legitimate death in the fight, and no one has a rezz for them and you wipe.

The goal isn't to make it so no one dies, the goal is to make it so you have to pay attention to not die. Way too many wrath encounters just require you to run out of the void zone, or keep jumping, or do other easy to MACRO things. Cataclysm raids will have more "random" and unpredictable things. Will flame jet A or B go off this time? What about the spawns from the back door?

I saw someone get brezzed recently that came back with full health and mana... thought that was a rebirth with glyph?

"Way too many wrath encounters just require you to run out of the void zone, or keep jumping, or do other easy to MACRO things. Cataclysm raids will have more "random" and unpredictable things. Will flame jet A or B go off this time? What about the spawns from the back door?"

Hard modes/heroic modes were like this in wrath of the lich king, as well as certain normal mode encounters like blood princes, lich king, professor putricide, sindragosa.

OOM healers? Save the rez for who needs it, a healer should be looking out for their own mana. If there's a nasty tank debuff, a tank, if everyone's getting hurt all the time a healer, or if you're not going to beat the enrage a dps. Good battle rezzes save raids.