As for the music genre, for me it goes like this:-
Back in the 1960s and before, I don't think anyone was describing music as Americana: traditional, jazz, folk, blues, country.... those were the labels in common use. You could describe Hank Williams, The Crickets, Woody Guthrie with labels like that.
Then folk-rock songs began appearing: the Byrds, The Band etc. "Folk-rock" was never a very popular term, perhaps because it was just a two-genre label and technically didn't cover, for example, an artist revamping Gershwin. So "Americana" became a better label to cover any artist who was paying his honourable dues to traditional American music, but giving it a post-sixties slant.
Like any term, its usage gets pretty fuzzy round the edges. To try and keep things clear in my head, I wouldn't use the word "Americana" for music that wasn't, afaik, described that way at the time. Of course, this distinction begins to break down with someone like Burl Ives, who just kept on performing right across the label-change I've outlined, oblivious to the grief he was causing to pigeon-holers like me. Maybe I need to rethink how I apply the word.
