The recent Ofcom report which stated that UK viewers are, as a proportion, more likely to own a DVR/PVR, was really promising, showing that 30% of viewers have one, as reported by InformITV and others. However the numbers have been questioned by InformITV based on a quick count of the numbers across each platform, estimating that the actual numbers are more in line with the US, around 20%. Whichever way you look at it, this is a good number of viewers and growing.
However, the InformITV report poured scorn on those persons who reported recordable DVD players as DVRs, and also ignored the other number of viewers who make use of PC or non-STB based recording devices. I am sure similar numbers of viewers in the US and other countries would similarly report such devices as DVRs, equalising the misreporting overall so I am sure that the reported numbers are sound. The justification for this is that the US has traditionally made it harder and harder for recording of off-air TV shows unlike the market in the UK, where the battles about advert skipping and analogue holes have simply not taken place. This is in part due to the size of the Sky TV influence, and the impact of Sky + on the market in the UK, leaving UK consumers to record what they want and when they want it. Add on to this the open market that Freeview, Freeview+ and now Freesat/+ gives (with the increased digital penetration), and you have a perfect storm that is growing the DVR into a no-brainer for most consumers. 
The use of recordable DVD players has also been popular because of the ability to interconnect these units over high quality (relatively) SCART connections to standard STBs and in-built tuners at the same time has meant that Analogue recording has been the second tuner in the home for many.
DVR/PVRs are here to stay, and it is only the viewer education issue that is slowing its further growth to the point where I expect every home to have one if not two, although a multi-room solution and in-home networking capability will assist in that growth I believe.
