Great documentary, and although singing isn't a quantifiable skill (best ever? Well...) I can agree he was one of the best I've ever heard, and although prone to some whacky behavior (to put it mildly) his stuff utterly holds up. A fave album for years has been "Nilsson Sings Newman" which I often force people to listen to and very enthusiastically recommend. I have pretty much all of his stuff including a 3 CD set from BMG in 2000 called "Legendary Harry Nilsson" which has 2 sides of 17 cuts and one of 16...lots of Harry...although missing "You're Breaking My Heart" since the perceived obscenity would seemingly harm people's fragile brains...hmm...