For sure there needs to be a way to listen to songs you don't want to own, but it's called [em]radio[/em], not subscriptions. Apple has the ability to reinvent and reinvigorate both radio and peer-to-peer, potentially turning every copy of iTunes into a [em]licensed[/em] narrowcast station. Give me the ability to turn these into podcasts for my iPods and subscription is dead as a dodo.
Subscription Model Killing iTunes? Yawn.