For what it's worth, here's one listener's experience. Since I signed up for Spotify about 6 months ago, there has been a serious decline in my jazz radio listening. I used to listen to radio primarily to hear new sounds - jazz I hadn't heard before. Things discovered in this way often led to album purchases - or should I say, album acquisition? On Spotify there is enough unheard stuff to keep me discovering new sounds till the end of my days and I listen so much on it that I have little time left for jazz radio. Album acquisition has also been largely replaced by the adding of good new discoveries to my Spotify playlists. These, however, may not be entirely reliable - often tracks are omitted from albums and tracks can disappear after a few months, so there's still hope for CDs!