Should Apple take a chance with music subscriptions?

It's hard to figure why anyone would do any prospecting in the stony terrain of digital-music subscriptions.

This week, Best Buy acquired the remade and beleaguered version of Napster for a song. The deal is likely bad news for RealNetwork's Rhapsody, the current engine behind Best Buy's digital music store and one of the pioneers in music subscriptions. (I wrote a sidebar about the troubles RealNetworks' Rhapsody may face if Best Buy walks.)

And don't forget, the Yahoo Unlimited subscription service was shuttered earlier this year.

The all-you-can-eat music services are the ones getting chewed up. So why do rumors persist that Apple is interested in getting into music subscriptions? In March, the Financial Times reported that Apple had talked with the top record labels about the possibility of launching a service that would give iTunes users access to its entire library in exchange for paying a premium for iPods or iPhones