What if:
Pandora technology is integrated into iTunes and iTMS. For 15 €/month you can subscribe to three pandora stations (which are defined and modified via iTunes playlists and ratings), whose songs you get like a subscription based service. Protected AAC files that expire once your subscription is over. BUT the selling point will be: you can select 10 songs each month that you can keep like any other song purchased at iTMS.
Subscribing to these pandora stations is as easy as using a podcast, in fact the streams are podcasts with, say, 10 new songs a day.
Just dreaming.
FYI,
ITunes integration from the pandora player already exist.
Basicly -
1) open the pandora player using the time shifting app found here
http://www.hak5.org/forums/viewtopic.php?t=983
2) enable ITunes integration
3) define playlist name in the save dir field
4) ITunes playlist created dynamicly and pandora tracks are imported