It works pretty well. What I like is that it takes the songs you don't listen to that much from albums and put them in the playlist so they fit nicely in there. I've find it works really well with endings and starts. If a song ends abruptly, the next song is usually building up its intro. If it ends slowly, the next song can be instantly fast. I really really like this. I don't see how it will become more clever by user submissions though. I think the intelligence thing only applies to the recommendations you get from the iTunes store