This guy is more than just an Internet celebrity though, this guy runs a search engine as a competitor to them -- why are they watching his blog? (Or did they come across it by accident?)
It might also just be that some people who work at Google who know some people working on Gmail read HN or his blog. They seem like the right demographic :)
it would seem to me that as a competitor to them, it's obvious that google would pay (at least a little) attention to gabriel's blog. of course, i'm sure getting mentioned in a NYT blog didn't hurt, either.
Speculative comment ahoy!