The allthingsd article suggests a good fit with Twitter...

...specializing in very short clips — a few seconds apiece.

And from the Vine.co home page...

No editing. No rendering. No post-production. Video has never been this fun.

This is certainly why lots of Facebook users like to upload iPhone still photos to Facebook, so Twitter may have the right idea. I've always felt that there's nothing so useless as an isolated video shot, and Twitter/Vine may either confirm that or prove me wrong.

Can't resist, btw, pointing out the overlap with "Hollywood and Vine", a well known Hollywood intersection that was synonymous with the center of show business in the US. (Could be Vine.co will revive the phrase, but with less emphasis on production value). ;)