DVR's are still out of the financial reach off many people. Maybe its because i'm fresh out of uni and most of my friends got useless degrees, but in my group of friends I'm the only one with a PVR. Shaw up here in Western Canada still wants $600 for a HD-PVR, which is out of reach of alot of people.
Even with a PVR I find myself watching alot of live television for two reasons. One, you really need to watch sports live. Two, my cable signal is garbage and if watching live a sudden drop out for a second or two is an annoyance, but if I'm watching on on the PVR the recording fails. So while the PVR is great to set a bunch of stuff on season passes and have something to watch in my free time, its just not there ... at least from my provider ... to depend on for something you 'have to' watch.