That's an interesting question. I think there are a few factors. Meyer was one of the pioneers of modern web development (many people here have mentioned using

That's an interesting question. I think there are a few factors. Meyer was one of the pioneers of modern web development (many people here have mentioned using his `reset.css`). Related to that, many people on HN are or were web developers, meaning that he has a built-in brand among that group. Lastly, he has been very public about his daughter's disease and his family's struggles with it. It's cliche to say that social media tends to be about self-promotion. His tweets and blog-posts on the other hand have been real, emotional, and sad. That's rare (and experimental), and his celebrity status within a population active on social media meant that many people not only knew about his daughter but actually became invested.