The good: Getting 3 shadow orbs from Mind Blast glyph helps Shadow immensely in the opener. Having an extra 2 orbs is a strange choice, but orbs are plentiful and it helps create double devouring plague or devouring plague + psychic horror combos. The game plays a little slower, which helps Shadow not get gutted in the opener in 2s.
We'll have to wait and see on more balancing to see where Shadow Priest goes. The damage is crazy good right now and the off-healing is powerful (but feels clumsy spamming Flash Heal). Yet, it feels like once Psychic Horror and MB bug are balanced/fixed, Priests are going to really feel how weak their CC is.
its really insane how bad spriest cc is to begin with, a nerf is really uncalled for.
the class has already gotten to the point where doing anything other than pumping damage in any scenario feels like a mistake as all other aspects of the class (utility, heal, cc) have been nerfed so hard. its so refreshing playing something like mage/druid/hunter/rogue/lock after playing a lot of spriest because you can respond to players on the other team doing stuff in multiple ways.
on my rogue i anticipate/see a trinket and i get to quickly pick a reaction based on how the game is going and what my team has or the enemy team has. a lot of the time on my spriest i see someone pop a trinket and im like "cool" then continue to pump raid dps while my teammates clone/poly/deep or whatever it because wasting a long cd fear or silence on that target would likely ruin our kill attempt 10 seconds later.