HBO OnDemand is the best! If I miss the show (Deadwood, Sopranos, etc.) They will have the latest show available starting the next day. That way I don't even have to worry about DVRing the thing and can watch that show any time that I want.
No doubt, man! I was going to buy a Tivo just to record the HBO series that I watch with a friend of mine. We only get together every couple of weeks to watch things like Deadwood/Sopranos. With OnDemand (I have Comcast, btw) we watched the first four Deadwood episodes in one evening. The whole series was up there for awhile after it ended.
I now have the PVR cable box supplied by Comcast for the HD programming and I've only used it once. Granted, I don't seem to watch as much television as most users here, but I have found OnDemand to be great.
I would love to see more things available using the OnDemand thing. Even if I had to subsribe to a premium service for it. I think I have access to everything currently showing on OnDemand, but I actually subscribe to everything. I think my friend (who doesn't get HBO) has to pay a nominal fee to watch things from HBO OnDemand.
I just hate to be chained to my television or follow a schedule. I suppose I could just learn to actually use the PVR. I am really sad I haven't seen Lost