I suppose if we look at it as a medium for art than it's different. I saw a lot of what I described as utilitarian.
I use Twitter in the same way - it serves a purpose: I can connect with people or groups I need to ask questions of. I can share interesting stories / ideas that I find. I use it as a portal to those blog posts you mentioned, not as a replacement for them.
Outside of the art angle, I don't see myself "tuning in" to thumb through random 6 second videos. The Tokyo taxi scene isn't very interesting to me outside of context within a larger story, EXCEPT as a piece of art I can perhaps appreciate for 6 seconds and move on.
Like I said before, could be just me, I'm glad people are finding and enjoying a creative outlet that clearly speaks to something they enjoy doing :)