Actually, I’ve thought that almost the opposite of the problem Joe describes (that of personally-identifiable viewing information, PIVI, being collected) faces MythTV. I think it’s extremely interesting that Tivo can tell us that ice skaters falling are the most rewound/re-watched moments of the Olympics or that people are watching The Daily Show with Jon Stewart more than anything else during the week. See Tivo Central. That’s valuable sociological/pop-culture data that isn’t captured for MythTV users.
It seems easy enough to solve since MythTV is a free software project. We can easily get the interesting data and avoid the privacy concerns: MythTV developers (or you!) could write a plugin that allows MythTV users to opt-in to anonymized data collection and then a network of volunteer servers could collect and display the results. The plugin would also be free software and those with privacy concerns could inspect the code and be assured that any personally-identifiable data was being stripped out. However, since MythTV is both free and no-cost, there isn’t billing data such as address and credit card information to begin with. The only personally-identifiable info that could possibly be collected would be IP address and it’d be easy to write the plugin so that it required Tor to anonymize even that.
This viewing data is interesting in so many ways. I think what shows a person records may say a lot about them. Knnowing what shows most people are recording also lets you know if you’re missing something worth checking out. I’ve even thought that a match-making/dating service would benefit from collecting individualized recording data and then matching people based on it. Even if romance didn’t develop, they could certainly agree on what to watch. (I’m publishing this last idea now in the hopes of thwarting any future business-method patent based on it.)