The advantages of going deep discipline vs holy for PVE seem to be:

• Power infusion

• Stronger bubble

• Bigger mana pool

• Lower mana cost for instant casts, so more liberal use of dispel, renew, bubble, fade, nova

• Threat reduction. Seems useful if you're putting bubbles on a lot of random people

Did I miss anything? Was this stuff good enough to make it worthwhile for raiding or 5 mans compared to holy?

Also, one side note: iirc, during vanilla, bubble had some bad stigma, and I think this was partly because healing meter addons could not attribute bubble absorption to the priest's effective healing. I wonder if the 7.x client will have the same behavior.