I think, so long as the traditional stuff does not get eclipsed completely, it can be a wonderful thing when artists take a few liberties here and there. Sometimes, they are helping to bring new listeners to traditional folk music. I know from my own experience, that, without Jethro Tull as a teenager, I'd likely have not found traditional folk music. I realize that Tull is a far cry, but they were a great "gateway" band.