Her left arm and legs have too much reddish orange in them, and are very bright in comparison to her face that looks dark and green. Very unbalanced. Also, looking at the before and after, I don’t care for the way you reduced her waist to an unnatural comic strip look, but that’s probably me... Maybe.
Nice shot and attractive model. I agree the skin is too saturated/orange-y. Maybe bring down just the red channel in your levels adjustment? How did you light her?
Oh yeah - just noticed the waist reduction. Don't think she needed that. She's already slim enough.
Great colors and nice PP but for me, I find the BG a touch distracting; I'd defocus it a little. The hair light's not doing much for me either - it looks like it's there purely because that's where it always is in a 3-point lighting set-up. Also, she's a beautiful model but the pose is not the most inspiring.
The mouseover confirmed my first impression of a over-done waspwaist. Not only too small, but where it is the narrowest has changed (lower) in your shot.
The background of grey is good for a black dress. The pockets of blue around the edge of the frame is something I'm not sure I like - mixed feelings actually.
The bottom line is the result is very pleasing. Well done.
Apart from the comments above on the postprocessing, the composition does not appeal to me. There are so many distractions and elements that lead your eye out of the image that all attention is drawn away from the dress, that according to the title is to be the topic of interest.
I'll give my ultimate compliments to this picture:
Love the light and shadows
Love the Post work
Love the body shape
Love the beautiful girl
Love your skills both for the shot and the PS work.