This is so gorgeous. I love the slightly ethereal qualities that puts Celestia in an uneasy balance between the material and the mystical. This picture takes those qualities from the Cutie Mark Chronicles scene and intensifies them.
Oh...my...golly...(did I really just type "golly"?)...GOODNESS!! That is absolutely AMAZING. I feel bad that you're probably getting tons of "___ Favorited 'I am the dawn'" notifications. ...Add another one to the list! Really, REALLY great work! I love it! Just...wow.