I am blown away by the number of people on HN and elsewhere who are posting about "how they must be doing it" and then calling it unimpressive or a technical dead end.

Reading the blog post, I now know how Notch would approach building such a thing, and that he thinks his approach wouldn't really work. I still have no idea how Euclidean's implementation actually works and neither does anyone else who I've seen comment on their demo video.