There isn't much to say about this other than, Finally. According to Business Week, Sony BMG has decided to sell some of its digital music without attaching copy-restriction software, making it the final major label to abandon ridiculous, impractical, anti-customer restrictions in its products.
Last year Warner Music, the Universal Music Group, and EMI decided to leave out digital rights management, or DRM, in their songs.
Record labels had once considered these restrictions -- which limit how often, or for how long, or where, or on what devices, or in which countries, or during what phase of the moon you can play your songs -- necessary to preventing piracy online.
Witness the scheme the labels and Apple cooked up for songs in the iTunes store: you've got to burn your songs and then re-rip them in order to play them on non-Apple devices, and you're limited in the number of computers you can put them on.
But because the music business has long sold most of its music without restrictions -- on CDs -- the digital shackles were never going to stop piracy.
Thus pirates flourished while the law-abiding among us were frustrated by things like Microsoft's "three days or three plays" policy on the Zune (a DRM scheme that deviously cut off your access to songs you traded with your friends, killing the potential fun of that device).
The labels, one should note, aren't changing their plans now out of a renewed appreciation for their customers.
Actually, what's happened is quite ironic. It was the industry's own DRM mandates that tied many music-lovers in to Apple's music storefront (we all had iPods, and the only way to buy digital music for the iPod was from Apple).
Now Apple's become too powerful for the labels. They need an alternative distribution channel -- they want to get music to our iPods, but they don't want to go through Apple to do it.
The only way to do that is to offer retailers like Amazon the chance to sell songs as plain, unrestricted MP3s, which are iPoddable.
Shakespeare coined a phrase for this sort of plot-twist. Hoist by his own petard, I think it was.