git/GitHub are not for code. They are for version control. Most common applications of git are in software (since things like MS Word et al. have their own implementation of revision history within the software package), but it's not limited to such.

Suppose he comes up with a better way to build the device. It would be good practice to have all versions available, something that isn't as easy to do with a website. Additionally, his target audience is people who use vim, which probably has a reasonably large overlap with git/GitHub users.

I hope that it does not become a trend to create repositories for every blog post. Github is not a personal blog, and I don't think it should be used as such.

If you're a coder you probably already have a GitHub account maybe not a web host.

Another benefit of hosting something like this on GitHub is you get instant scaling in case you hit the front page of HN (or similar sites) and suddenly get thousands more visitors than some blog software can handle.

I myself am thinking of hosting all my school files next semester in Github. Its free, and fast, and, well, Git.