I hope that blizzard makes it possible to toggle off shadowform. The reason why, is that my wife played a shadowpriest, and she got really upset about it when she tried it in alpha. She likes transmog, play on a RP server, and I understand why she want to be able to toggle it off. She collects pretty dresses that she uses for RP, and constant shadowform ruins that.
Would be cool if SP automatic activated shadow form when in combat, and just developed as you gain insanity.