So it can be a separate tab on your character gear screen, with only helm, shoulder, gloves, chest, pants, and boots slots. You can toggle this on and off (off means your main, actual gear will determine the way you look) on that tab, and if you leave it on without putting any gear in vanity slots your character will appear naked.
This gives a lot more freedom in the way your character's looks can be customized (way more than dyes alone). I'm sick and tired of everybody having Vile Wards, and almost every mid-high level DH looks the same with Natalya's set.
What do you think?