This picture draws a lot of attention and if it weren't from the vector lines drawing attention to Miku, I'd be lost in the pretty collection of glitter around her.
Miku herself is very well done with her clothes and the hair on her head, but the thing that gets me is her twintails. Personally, I prefer Miku with poofier twintails. I dunno if it's because of the official boxart or a lot of fanart with a lot of hair but whatever. That's my opinion.
Miku's eyes also seem to be rather pale from the light around her. To me this makes her look undead and combined with her facial expression... well let's just say "Where is my shotgun?"
Miku's proportions are all correct by taking a quick look at them and whole thing stands out in comparison to many other artworks. Overall I'd say it's well done. Not the best artwork I've seen here but certainly better than any of mine... for now...