Err, that didn't look all too sturdy. One major storm looks like it could cave the whole thing in. This quote in the building section didn't make me feel at ease:
30 or so small trees and a bit of chainsawing later. Lift logs, prop up, nail together and continue until no longer wobbly.
Continue until no longer wobbly?! I've seen better hobbit houses being built on the internet, complete with REAL supports that are just as good environmentally.