For all their talk of anti-homogenisation Blizzard are leaning pretty hard onto forcing everyone into the same talent choices.
Being of the non-QQ variety I will fully admit that IA was too powerful. In my most recent WoL report for Festergut, I had a 70% uptime for it. At ~25k HP (estimated, then rounded for simplicity) this equals 1250sp when procced for an average of 875sp. That's massive for 3 points. Granted not every fight has a Festergut-style mechanic of raid damage, but I still believe the mechanic of this talent to be (previously) too powerful.
That being said, they went from a talent that was amazing should you have a raid healing discipline priest, to a talent that no mage with so much as a slight capability of critical thinking will ever include in their primary build. Nerf it? Sure. But why on earth would they completely destroy it?! I am surprised there is not ONE raiding mage that works for Blizzard that said, "Whoa... slow down. If you implement this precise change, you are forcing every mage back into the same spec!"
I can readily see them nerfing it even as far as ~1% of maximum HP. A 250sp proc here and there would by no means be obscene and I think it would be just enough to make it a 'flavor' talent that would have us debating it's merits v. MA or Stability.