Man, this is really beautifully done. Something about the uniqueness of the perspective (the "looking out of a cave" feeling that BryceEllicott mentioned) is just so absolutely neat and unusual that I can't take my eyes off it. The sort of out of focus, grainy look that the rock in the foreground has gives it a photorealistic quality, and the fact that the person (or animal, or what have you) whose point of view this is from is peeking out from inside a cave just unfolds a whole little story about the picture in my mind. Excellent work!
The architecture style of the buildings has a nice alien feel, and I like how the glints of light continue down into the canyon. The perspective is interesting, like looking out from a cave or some such. But the black spaces sort of feel like they are in my way - I want to put myself outside and see the scene fully.