I've become increasingly aware on sites such as MySpace that there are all kinds of sub-genres which I had never met before. Such as acid folk and psychedelic folk. When I've had a brief listen to their MySpace offerings I've been at a total loss to work out why the F word is applied to their music at all - but it is. I've given up worrying about it, and wondering why they feel they can use the word in such a cavalier manner when I don't feel I can about my own music... but there it is. Words, definitions and categories (oh, go on then, GENRES) change all the time. People need to put tags on things so they know which box to put them into. Me, I'd be happy to be just plain ole music, but there we are. I've adopted the circumlocution of "performs mostly on the folk circuit" to avoid calling myself a folksinger or a writer of folksongs, but maybe I should just get on with it.
As has been said by others, "folk" is almost as meaningless a descriptor as "celtic". I'm not going to lose any sleep over it - but, as Tom says, I think we need to remember to credit where songs or ideas came from, if we know.

Anne