As for the Scandinavian thing, I've been playing mostly Swedish dance music for the last few years. The "feel" of the tradition is somewhat different than the American, British and French music I'd played before. It's almost like the traditional music is more conscious; musicians regularly know the names of the composers of tunes that are a hundred years old or more, as well as the name of the person who came up with the version that gets commonly played. This seems to be a part of the tradition in the minds of most of those who play the music. Also, newly composed tunes -- if they do what dance tunes are supposed to do -- get accepted into the traditional repertoire quite easily.