* Google isn't a domain registrar. If they were then one would hope that google.com would be registered under them, not markmonitor.com (a popular corporate registrar)
* The server hostname is a subdomain of amazonaws.com and doesn't require registration.
* In fact, the entire name is autogenerated from the IP address using a simple substitution rule.
* I'm not sure how Google finds these, because their own "what links here" doesn't turn anything up.
* Side note: while searching for backlinks in Google, I noticed that this article seems to have been copypasta'd to a dozen other blogs. That's SEO, baby!
EDIT: Damnit HN, you look like reddit, why can't you use a sane text preprocessor like reddit?