I'm still a newcomer to the PVR (or is it a DVR?), having only taken the plunge in March 2009.
As you all predicted, it has radically changed the way I watch television. In fact, I don't watch anything in real-time anymore, unless it's a live sporting event. Appointment viewing for all other programming has completely disappeared.
There are two primary reasons for this switch: convenience and ad avoidance. I decide when I'm going to watch The Simpsons or Lost or 30 Rock. We press play when we're ready, and we fast forward all commercials. If it's something we want to watch close to real-time, like the Academy Awards, we start it about an hour after it starts so we can ignore everything television advertisers throw at us.
Some shows we'll watch On Demand with Rogers on channel 309. We're currently going through Jason Schwartzman's Bored to Death that way, but we can pause, fast forward, etc. There are other programs we deem "time sensitive", like Saturday Night Live and 60 Minutes. We try to get to those within 48 hours of airing, whereas I've still got Family Guy episodes from November to watch.
If it's not sports, I don't see the ads. Because I don't see as many TV ads as I used to, I find I'm less tolerant of them. The Pepsi Cheer Nation ads, for example, have me infuriated, and I'm in full Pepsi-attack mode. We'll see if the Star prints the article I submitted.
The PVR must be the worst invention as far as broadcasters are concerned. Their revenue comes from advertisement sales, and the PVR has made ads invisible.
It's just too bad my only defence against that insulting and sickening Pepsi campaign is the mute button.