Looks like the musicians have started to cry "foul" over DRM - this is exactly the kind of thing that the labels fear most. In a NYT Op/Ed piece, Damian Kulash Jr. (of Ok/Go) has spelled out the problems succinctly:

The Sony BMG debacle revealed the privacy issues and security risks tied to the spyware that many copy-protection programs install on users' computers. But even if these problems are solved, copy protection is guaranteed to fail because it's a house of cards. No matter how sophisticated the software, it takes only one person to break it, once, and the music is free to roam and multiply on the peer-to-peer file-trading networks.

That's the technical problem right there - none of these schemes are break-proof, and the people willing to break them will do so quickly. Meanwhile, the bigger problem is with the people who legally buy the music, and then can't do what they want with it:

Meanwhile, music lovers get pushed away. Tech-savvy fans won't go to the trouble of buying a strings-attached record when they can get a better version free. Less Net-knowledgeable fans (those who don't know the simple tricks to get around the copy-protection software or don't use peer-to-peer networks) are punished by discs that often won't load onto their MP3 players (the copy-protection programs are incompatible with Apple's iPods, for example) and sometimes won't even play in their computers.

Conscientious fans, who buy music legally because it's the right thing to do, just get insulted. They've made the choice not to steal their music, and the labels thank them by giving them an inferior product hampered by software that's at best a nuisance, and at worst a security threat.

Damian then goes on to point out that having the music spread - even if some of it spreads illegally - is a net positive for the artists. More people hear it, and more people end up buying it. The attempt to lock it up merely gets in the way of the good people, and does nothing to stop the bad people.

Which is why all of these sorts of schemes - DRM for music, the absurd PVP-OPM thing that Microsoft wants to harm us with - these are all stupid ideas that get in the way of law abiding customers trying to legally use a product (CD, DVD, etc).