There's no specific point or statement, it's just "interesting data" that you can draw your own conclusions from.
For one, it's a nice overview of which YC companies are active on Twitter and which are not so much. Which are recently growing a lot, and which are stagnating.
It's also interesting to compare the number of followers to the number of following/tweets. We can see that Dropbox has very disproportional numbers, turns out this is because following @Dropbox on Twitter gives you a reward on their service.
I really don't get the point of this post, and I'm commenting because I care about knowing the point of this post.