I enjoyed this a great deal, although saying I'm thrilled would describe the anime wrongly. It's basically a calm, unbridled look into the fantasy of the writer. The story is something with the creativity of a child, while not being overly childish.
The animation, quality wise, is quite bad. Everything lacks in detail and shades or often left out. However, the animation style is different from the norm and more alike to some of the old cartoons or picture-books out there, giving it a charm of its own.
The music is reserved, but fitting when used, giving off a calm, magical atmosphere. Sound effects, a section usually overlooked for being bland, are noticeably well done and added to the experience. The voice acting is done well.
Basically, for those not afraid to sacrifice a bit of animation-quality for a creative story and quality sound effects, URSA minor BLUE is definitely worth checking out.