The Beeb wants to make its specialist music shows more attractive to the general listener so they don't lose their audience. Bringing in an established radio broadcaster (albeit one with an interest in folk), rather than one from within the folk world, is another step along the road.

The general flavour of the show is dictated by Smooth Ops who are in turn dictated to by the BBC. Mark Radcliffe will bring his own personality to the show and may have a little influence on the choice of music, but I suspect the music that is played on the show won't change a lot.