What I think is the most significant:
Syphon strike giving more mana in grit is a very nice change, no way about it, it's a great addition.
The Blackest Night is great when you know the damage is coming, really allows for skillful play.
Darkside's mana changes, even without the damage increase, is absolutely amazing.

My bad:
Dark passenger. Why? Just.. Why?
Defensive cooldowns outside of TBN makes me a sad panda.
Enmity and the well known VIT > STR issues.
Bloodspiller kind of sucks due to GCD and no extra utility from damage. Carve and Spit is better.
No more parry low blows.

The neutral:
I actually don't mind the blood price changes because of the changes to dark side. You'll usually be fine for enmity after throwing out 4-6 abyssal drains and probably a quietus. Getting a syphon strike or two in there isn't too bad, the change allows more control. I do prefer the old BP by a long shot of course.