Same as always, because people upvote it, probably it's interesting to a bunch of people.

> What to Submit - On-Topic: Anything that good hackers would find interesting. That includes more than hacking and startups. If you had to reduce it to a sentence, the answer might be: anything that gratifies one's intellectual curiosity.

Whoever "people" is.

How many upvotes (in orders of magnitude) are needed to get to the front page is still a mystery to me.

I wonder if there are "slow days" on which it might be easier because there is less voting in general.