Since learning how to use the iTunes "Sharing" feature, I've grown accustomed to being able to access the music from my Upstairs Computer on my Downstairs Computer via my home wireless network.
It's a great feature, one that makes me look at having to rent a digital cable box for every TV with a jaundiced eye. Why do I have to have every TV plugged into a cable, and why do I need a separate signal decoding device for every TV? And, why do I always find it more convenient to check what's on TV via my computer and TitanTV? Also, why do I have to subscribe to (and pay for) ten times more cable channels than I really use?
I know, there are several differences here. The digital boxes have no storage and are accessing remotely stored (or streaming) programming. Even if I get a DVR box to replace one of the digital cable boxes, though, I won't be able to straightaway access and control its recordings from other TV's without having to buy more add-on in-house networking equipment from a third party, which seems crazy. But I certainly don't expect my cable supplier to make in-house networking easy as long as their revenue is tied to the rental of physical boxes and their ability to demand premiums for tiered service. (The idea of having to "subscribe" to a channel seems weird, too, given how easy it is on a computer network to select and activate sources for downloading, but that's another story.)
Much of the reason for all this is probably the web of legal, regulatory, and commercial lobbying interests that have grown up around the cable business. I was reminded of this while listening to Congressional hearings on C-SPAN the other day. Cable industry executives were testifying about their business. I didn't know what the subject of the hearings was, but as I listened to the faceless voices in my radio earphones as I walked the dog by the creek near our house, I realized that the words and phrases they were using were all about preserving revenue streams, accommodating contractual requirements with providers, and allocating scarce bandwidth, NOT about viewer choice or selectivity. This is what local cable monopolies have given us -- a system designed to limit competition and innovation in order to preserve a monthly revenue stream.
Fortunately, alternatives are evolving. They're evolving slowly and painfully, and special interests are seeking to hobble them with restrictive DRM and industry-enforced restrictions on analog signal display quality. If we can prevent industry-government collusion on the squelching of technical innovation, there's a chance that media networking will evolve freely.
But I'm not holding my breath.