In terms of style and content, this scratches every one of my perennial itches. I love the music, love the visual style, love the concept... good stuff.
I have to agree with some of the other commenters, though, when it comes to areas for improvement - the jumping sound is terribly annoying considering how much jumping you need to do, the uncommonly slow pace and occasionally unresponsive controls make it needlessly difficult to time jumps, and the difficulty certainly warrants a checkpoint system.
On the whole, though, it's a solid game with a lot to like. I wish more developers were this devoted to aesthetics and style!