I'm not yet ready to give my full expose on why I think this whole thing is bullstuff yet, but...
Octree isn't necessarily the hardest thing to implement code-wise, but it is very time-consuming and requires a great-deal of knowledge in other areas, and employing it effectively takes a lot of skill. You can easily go to Google, search for "octree" and get a million tutorials/open-source libraries for any game engine or programming language (Unity has a great open-source octree library), but that doesn't mean you'll actually make something decent with it.
While it's possible that an experienced programmer who has worked with data structures and done some basic computer science/scientific notation would be able to make something to equal or better Blockland's implementation, there's no doubt in my mind that these guys are not at that level and won't be for some time.