I honestly don't see what's so great about this.
Okay, yes the animation for the scenery is absolutely gorgeous, but the characters look absolutely bland in comparison. The ending seems rushed and undeveloped, the characters are likeable but don't stand out in any way, the girl focused on in Act 2 serves no real purpose, and by the end the main character just seems kind of creepy and obsessive.
Pretty much the only good that I've seen come out of this is the nice backgrounds and the quote "At what speed must I live to be able to see you again?"