Very good point. However, I'm certain any cpu-locked DRM will fail thanks to the open source movement and the vast amounts of people who are amply aware of DRM and will do whatever to kill/disrupt/crush it. To date, no single massively adopted DRM system has been crack proof.
With the likes of virtual machines on PC's and OS's running on top of OS's (Cygwin on Windows, etc...), you'll see people simply run applications at a layer above Windows and Intel Hardware DRM, completely defeating a total-DRM-media-protection concept.
I think the only hope DRM has is if content providers (who wish to curb unlawful distribution) used invisible watermarking. A single media file is watermaked in a way that ties that particular file to a purchaser. If pirated copies end up on the net, then finding the source of that copy is a no-brainer.
Of course you have the problem of transfer rights (which could easily be managed, say, if you wanted to resell your copy to someone else, with today�s technology). And it does only take one copy to get leaked to spread everywhere (intentional or unintentional - lots of people have spyware on their systems that could chuck a file onto P2P). This has lots of flaws and by no means is perfect, though it might lessen piracy, but not to the extent that media companies want (pre-P2P days).
A plus would be that such a system wouldn�t cripple ones abilities to move and manage their media as they please (PSP it, CDR it, iPod it, Xbox 360 it, Linux it, etc�).
The only way for the media industries current method to work would be to lock down every aspect of everything, including the photons that project out of your TV, and the sound waves that emit from your speakers. Current forms of non-DRMed media (CD�s, DVD�s, broadcast TV, etc�) would all have to be killed off entirely. Past instances of non-DRMed technology couldn�t be entirely destroyed, so such a system would only work for new content.
Still, you have the photon and sound-wave issue. There�s no getting around that. ;)