I watched the documentary a few weeks ago and thought it was really fascinating. Truth be told, I'm a lurker/occasional poster at the message board and website where the entire Marwencol saga has been posted over the course of the last 6 or 7 years. It's a very involved, somewhat "stream of conscious" photo story and Mark has done at least three major narrative "resets" in the time he's been doing it. Even having followed Mark and the Marwencol saga from early on, I still recommend the documentary.
I have this idea of doing similar town one of these days but other life priorities keep getting in the way.