Here's a suggestion I just sent to Apple. Anyone like it or even care to comment?
The suggestion I have is for us to be able to load the ITMS, hit the play button and have iTunes pick tracks in a random order and play the 30 second preview of each one. This way, we all get to hear some new music that we wouldn't otherwise think of listening to or buying.
Obviously, while the track is playing, the snap-back arrow would take you to the song/artist page where you could buy it, but another feature would be for iTunes to have a menu containing the last 5 or 10 demoed songs so that you could go back to a previous song (whose name you probably don't know if you've never heard it before!). That way, there's probably more chance of you buying music you've never listened to before.
Anyway, tell me what you think.