I really like your use of light in this one, and your colorchoice is nice...not too cold, but not overwhelmingly warm.
Your wings are missing a few joints, and the feathers need some research (birds have about 4 or 5 different kinds of feathers on their wings, each different shapes and textures).
But, overall--nice pic! :)
This is really beautiful. The wings look strange, but the horse anatomy is really good, and so is the idea. Nice lighting. =D