Gosh...
I love those kind of flashes that make me feel warm inside.
Graphically, there there wasn't much to look at, the simplistic nature of the animations matched the simplistic nature of the song. In many cases, that type of realtion is so much more important than a mis-match between audio and visual attributes. I appreciated the fact that you used a 3-4 frame graphic for the purple figures at the beginning of the movie. That kind of Squigglevision is a key note that you were aware of the typical attention span of your audience.
There was no violence in the movie as none was really needed. Hence, your use (or in this case, non-use) of violence gets you a ten.
Here's my biggest complaint: the entire file size as a whole was less than 1 MB. That left plenty of room to optimize the quality of the sound clip that you used in the animation. I'm not sure if you were attempting to avoid an excessive loading time. However, I still found the quality of the sound much too low to really enjoy. An extra 24kbs wouldn't have hurt, but that's just my kick ass opinion.
Still, when the space man (*and space woman) came into the scene, the flash became magical to me. Maybe I'm just a sucker for cute people floating around astroids--but I certainly know what I like--and that was it.
So overall, the graphics were still were not too complex--yet the supporting attributes of this flash clearly showed me that you were going for a specific style. The song was a great choice--and perfect length as the the entirety of the animation ended on a crisp high note. I didn't necessarily laugh out loud, but there was an emotional feeling that came over me in this animation. That alone makes any cartoon great.