Yeah, I saw this one a while ago. For people concerned with the plastic leaching, he suggests coating the inside of the bottle with a thin layer of beeswax. I don't know if I'd do it myself, either, but it's definitely interesting, and I really like that it potentially opens up the practise to more people.
At the end of his latest (as of a couple weeks ago, anyway)
video there was a clip of him pulling one of these bottle hives out of a hole in the ground, so it looks like his experiments are ongoing.