"not only resulted in the invention of the digital video recorder"
Is this not an "obvious invention"? People have recorded to tape for decades. Back around 1996, my little 75MHz Pentium with a TV capture card was capable of recording broadcast video. The only drawback, due to the machine's specifications, real time video it was something silly like 176x144 in a really lame codec. However by '98 DVD recorders were on the market. Pricey, but showing that full-screen capable video hardware was a reality. Recall, also, that the Digibox with it's EPG system was launched in 1998. Therefore, it would not be a leap to think that somebody would think to use some video DSP hardware hooked to a harddisc as a RECORDER. Indeed, my later, faster, Celeron box (from '99) with video capture card used to do me recordings at 320x288 (again, limited by raw grunt) until I got myself a dedicated PVR, the Neuros OSD - which is *exactly* what I imagined - a video DSP to record the input and spit digital to a USB stick, SD card, etc. It, of course, turned up a lot later, but the concepts were not new. What was new, perhaps, was the miniscule power consumption. It was a choice between that and a harddisc-enabled DVD recorder. I *so* made the right choice!
Therefore, how is the idea of using digital means to record telly not obvious? The main hurdle, frankly, was waiting for the hardware to catch up with imagination.
Tivo, on the other hand, can claim some degree of innovation not just with a much better scheduling system than the likes of Sky's EPG, but also with making it friendly enough that people would be willing to pay for it. I wonder, though, if some of the innovations are also fairly obvious? Sky's EPG allows for linking and scheduling, and if they had decided on increased metadata, I don't doubt it wouldn't be too hard for a Digibox to "suggest" programmes you might like based on what you're watching, stuff like that. But no, it seems like Sky's EPG is pretty much aimed at the lowest common denominator. I was given a Sky+ box. Can't use it, don't have a Sky+ subscription (and unlikely, given I live in France). It works as a power-hungry 'normal' Digibox. I'm a little upset to see that ten years down the line, the EPG hasn't changed one single bit. <sigh>
But hey, if Tivo want to believe they *invented* the digital video recorder, then go for it. Doesn't really bother me. ;-)