Comcast is the largest cable operator in the United States, so DVR manufacturers are lining up to sell them their DVRs. What this means is that just as the Beta versus VHS battle of the late 1970s and early 1980s led to great innovations in VCRs, as long as there is this competition for DVRs, they will continue to add new features (and simple but important attributes such as longer recording times and the illusion of a DVR for every television set.
From the Comcast site on 6 March 2006, three DVRs are viewable:
This is the Comcast box as pictured at http://www.comcast.com/dvrselect/ on 6 March 2006. A demo was seen at http://www.comcast.com/dvrmotorola as of the date of this posting.
This is the Scientific-Atlanta box as pictured at http://www.comcast.com/dvrselect/ on 6 March 2006. A demo was seen at http://www.comcast.com/dvrsa/ as of the date of this posting. Time Warner Cable appears to show a Scientific-Atlanta DVR in a demo on their web site
I'm going to flip over to IPTV before returning to finish some thoughts on DVRs. The represent a portion of the revolution that is taking control of television viewing away from the program providers and giving it to the program viewers. IPTV is another revolutionary (yes, I said it and I mean it, "revolutionary") technology that will allow for ubiquitous video.
You may use this content (better still, argue with me!), but please cite my ideas as © 2006, Dr. Bruce Klopfenstein. Best viewed in Firefox thanks to Microsoft going its own way.