To go back to Dave's question about the difference between pop and c-folk, whilst I think most of us are agreed that we can't place finite boundaries, generally one way of looking at it is the first is written specifically for the pop-scene and the other is written for the folk-scene. Off hand I can't think of any writer who is consciously writing for both. For a pop song to enter the realms of folk is always possible and has always happened as far back as we have records for. This is perhaps where the contention comes in. How many established folk singers would need to perform a particular pop song for it to be accepted as folk by some of us? I say 'some of us' because everyone is going to set that parameter in a different place.