Uhmmm....... hehehehe some people say that is sad, while I say it is not. i guess you need to define what is "SAD".
Bale brilliant video montage ito to a specific theme. Isang intellectual movie about how distance put strains in relationships. My otaku friends says expert yung director sa mga ganitong themes and he is excercising his craft on this movie. A major plus in this movie is the art direction and the very good insert song. I will definitely recommend this movie to those who like to see top notch cell animation with a very meticulous attention to detail with nice short stories about love, "life" and "daily life".
(Honestly, Japan makes the best slice of life stories out there. I dunno about European movies but their slice of life/existentialist movies are soo boring, bleak and dark compared to the appreciative yet in-your-face-slice-of-life movies, dorama, anime you have in Japanese cultural products.)