There has been a legal tension going on for decades over the use of personal recording and playback devices to view copyrighted material. This includes content of all forms--particularly music, film, and text--and a variety of recording devices over time--cassette recorders, VCR's, TiVo's, and now CD and DVD recorders.
A fundamental issue is what rights can be restricted once a person has the right to view some content. It would be absurd to suggest that a library could restrict people, once they have borrowed a book, from reading the pages of the book in any order they like and even possibly skipping some of the pages. Such restrictions are more tempting for CD's, DVD's, and television, though the analogy to library books suggests maybe they do not really make much sense.
Most disturbing to me is the question of what kind of equipment people are allowed to own in their homes. Right now, I cannot legally play a DVD I own on a computer DVD player I own unless I additionally purchase a copy of MS Windows from Microsoft. Congress also passed a law to broaden the idea and do the same sort of thing for TV broadcasts via the "broadcast flag". The courts have struck down some but not all of these laws.
These ideas are analogous to Kellogg saying you cannot heat up one of their Eggo frozen waffles unless you use a Kellogg-certified Eggo-brand toaster (TM), or a bookstore saying that you cannot read a book out of order but must instead go through every page, one after the other. Worse, there has been legislation proposed analogous to making it illegal to even own a non-Eggo toaster. Such efforts violate the basic principle that people can generally use the stuff they own in their own homes however they like.
Overall, it's certainly important that we upgrade copyright law in response to changing technology. The bulk of the DMCA is important law. Small parts of the DMCA, however, reach tentacles of control into people's lives, and I worry that future rounds of development for this software is going even further in that direction. Surely, just because technology is getting better, the general public does not need to give up more individual rights about what we do in our own homes?