This was better than some of your other stuff.

The shading was done really well, if you get into flash this would make a good frame-by-frame character. Well done.

Although, this character could be a male.

Simple thought

Humanity.... Captured here is something great. The modesty, real female form, submissive pose, faceless anonymity....
your work has the reach to touch ones soul if one merely is open to be touched.

Issues

I feel the proportions are off, most females tend to have much more of a tapering at the waist, unless this person is pre-pubescent or just not an average female.

The other things that bother me, is the fact that as the eye travels down the amount of effort seems to dwindle, this makes me think you worked from up to down.

The leg positionings seem off, her right leg should be more solid, because there is no weight being held by either leg.

Her ankle is also contorted in an odd fashion, both feet are positioned weird. It's very nice despite the mentioned issues.

I don't think I have anything to add...

...that hasn't already been covered by others. She looks marvelous - great body language and posture, and I love the way her wings fall alongside her - it's like a cape of feathers. :3

oooh....aaaaah

I always enjoyed art featuring people with wings^_^