The NYT mentions one reason for this:
Where Is Apple’s Rental Service for Music? - Bits - Technology - New York Times Blog:Another "feature" of the new iPods is that they won't allow video out except through Apple's connectors. This is known as "plugging the analog hole", without this "feature" it would be relatively easy to create high quality copies of any video stored on an iPod.
...The technology behind this is that iPods need to have a tamper-proof clock in them so that content can be vaporized after its expiration date. The first models didn’t have this feature; the new ones do...
As the NYT suggests these technologies could be used to control music distribution as well.
These stories illuminate an interesting aspect of the copyright wars. They drive hardware sales. Each new front obsoletes a generation of hardware. Rather good news for Apple.
On a similar front, malware wars have been good for Microsoft. Malware mandates continuous software patches, and eventually malware driven product updates - like Vista.
Unanticipated emergent consequences, as always.
Speaking of unanticipated consequences, if I were the music industry, I'd be buying up used CDs and destroying them, while distributing new music by wire -- with full DRM support. Is anyone visiting used CD store looking for suspicious batch buyers?
What about the strategy of selling non-DRMd music on Amazon? Sure, it's good for beating up Apple, but I think it's really about destroying the CD. Buy up used CDs and destroy them, migrate consumers off CDs and onto the wire, then introduce robust watermarked identifiers so music can always be traced to the purchaser.
Not a bad strategy really, but it's sure to have unanticipated consequences. What will it mean when all thinks identify us? What will happen to the use and value of these identifiers? Will kidnappers force people to turn over their music collection? Will owners be able to "repudiate" their data, so it becomes unplayable? How will all this data be mined?
Lots of fun.