Note that the person who replied is not the person who owned the repo.
Either this is a case of Put the joke into air ten feet of north of me. Verify the result. or there was an issue with the repo.
If I was doing this I'd be looking at making a real repo with a magic string in its README.md - because there's a big difference between HTTP 200 on / for github.com, and everything working correctly so that magic string displays.
Interestingly I just got the following email 5 times in quick succession:
Dear <not my name>,
Your npm package, <a pkg I've contributed to>, has been added to npm cdn:
https://npm-cdn.com/pkg/<pgk>/
npm cdn relieves the burden of publishing your code to
a CDN in addition to the npm registry. All you need to
do is add a link to https://npm-cdn.com/pkg/<pkg>/ to
your README file so that the users of <pkg> could embed
up-to-date version of your javascript files to their
web apps without additional steps..
Since I've only contributed a patch or two I presume they got my email address from scraping GitHub.
Setting several CDNs to backup all the repos somebody could find? If that's true, sounds like an attack to me.
There was a similar thing a while back with Facebook cache servers killing little severs Iran attack simply told them to cache an image with `...png?random=...` on the end.
Still, waiting to hear from GitHub themselves - not too many things that can bring down a massive service like this!
When you can't reach this status page, GitHub is down. Otherwise it works fine.