For me:
Disc changes: I don't think disc will be properly balanced with the addition of mind blast.
Holy changes: CoH baseline is a fantastic change. Adding mind blast and pain? Eh. I kind of enjoyed just needing to worry about smite/holy fire/holy nova.
Shadow: Forget it. More S2M and voidform shit. Too bad we couldn't go back to wotlk vampire casters in an expansion that has actual vampires.
Interested in hearing more people's thoughts.