They're better than nothing. See them as moving pictures rather than videos.
I think they're the reason for why the amount of new Youtube videos has decreased dramatically. To some extent they have probably made the pictures from Instagram and Twitter decrease slightly too.
How long have Vine been popular? Just think about how many videos we've missed during that time up until 2-3 weeks ago. I had no idea that it would be smart to check vines until someone here asked about it.
Anyone who has collected even before that? The search engines that has been linked here only catch those who has a #-tag, which is just a small promille of the vines that are published.
I saved about 80 for just one weekend. Most of them were just crap though. But there's some gems every weekend.