A fine read over at Copyfight: Why Use DRM If It Doesn’t Work?. The following quote is a very important and interesting point:
What happens if the content industries start selling content in an unencumbered format? Well, technology companies are going to start developing products that use that content in new and innovative ways. Some of these ways may very well undermine the existing business models of the content industries. Without DRM the content industry would have very few levers with which to influence the consumer electonics and software companies. [...]
However, by insisting on proprietary DRM (well, under the DMCA it might not have to be proprietary), the content industries are in a much better position in negotiating how technology will be permitted to develop.
Rereading my earlier entry about Sony’s LIBRIe, this seems to make sense (even when talking about Japanese copyright law). By offering content in a proprietary DRM controlled format, Sony is able to control the development of digital devices that can read this format – which, of course, strengthens Sony’s market position.