I can’t tell you why this is the #2 story, but fortunately your comment is dead last so I’ve got some evidence the ranking algorithms are working appropriately.

> but why is this the number 2 story on HN?

Because it's interesting to a lot of folks.

Because transit infrastructure is really neat.

Because it is

(1) interesting

(2) new to nearly all

(3) something that people want more on HN

(4) on topic here

Because older articles lose karma and drop down the list. Not many new highly voted articles for today yet.

I've never known a hacker who didn't like trains and escalators.