Four music links from Arts and Letters Daily: a piece saying that there is no longer a popular music mass audience, another one blasting boring, pompous Bono and his inauthenticity, one on the durability of Goths (whose music I just cannot stand), and a review of a book whose thesis is that all performed music is by definition inauthentic.
My definition of "authenticity" in music: if you're doing it because you like it and it's what you want to do, it's authentic. If you're doing it just to make a buck, then it isn't. Pretending to be someone you aren't doesn't necessarily make you a phony; look at Bob Dylan, for example, who clearly loves all American music and whose lyrics are an honest attempt at meaning something. Yeah, when he was a kid he pretended to be a "real folkie" like Woody Guthrie, who of course wasn't a "real folkie" either, but that's a pecadillo compared to what Dylan's accomplished in his career.