I think that the DVR concept is a kludge. It does not make sense for people to record a show in their home when the recording is already available at the source. It is like saving a web page in your browser as a screenshot instead of directly downloading and saving the content. The DVR concept was great and the only available (digital) solution, but I think its time is up.
Video-on-demand is the right solution. And if it is combined with RSS (like podcasts are), then subscribing to a "videocast" would be equivalent to TiVo's very nice "season-pass" feature: you automatically get all episodes of a show every time one is available.
Comcast already provides video-on-demand, and other cable providers probably do as well. I have read that the phone companies want to get into this business as well. But obviously I would prefer an Apple solution. The Mac mini is very quite and very small, making it an ideal candidate for an Apple set-top box. It would be great if the Mac mini gets a built-in iPod dock. There are rumors around both of these. Hopefully the video providers allow their video to be synced to the iPod.
I hope Apple supports a subscription model as well as a buy-and-own model. Some shows/movies I like to watch only once and some I like to keep. And last but not the least, I hope that the subscription model is not more expensive than Comcast (which already is more expensive than Dish or DirecTV in my area).
UPDATE (2:00 PM, Jan 3, 2006):
From the first 4 comments below, it appears that I was not clear.
I am not talking about Apple just providing a device that you can connect to the current sources (cable/satellite TV providers). I am talking about an end-to-end Apple solution wherein Apple provides the device and the content, like their current end-to-end music solution.
Then Apple becomes the "source" and those who dump their current cable/satellite provider and switch to Apple would not require a DVR. That is why I wrote that I am hoping Apple would price this no more than Comcast.
And if this happens, then "switch"ing to Apple will have to be clarified: are you switching computing platforms or are you switching your cable/satellite TV service :-).
UPDATE (12:07 PM, Jan 5, 2006):
I am obviously assuming that Apple has access to the same content that the cable/satellite TV providers currently have. Else no one is going to switch away from their current provider. As for how Apple will deliver the content, I am assuming it will be over the internet (and/or over a WiMax network in the future).