Well, I would have bought a "two tuner for just one TV" HD DVR if it were available, rather than my ViP622. I only use it on one TV. Sometimes I think I might use it for a second TV and get rid of my 508. But realistically, I'll probably have another HDTV there before I get around to setting up the ViP622 in dual mode. So I guess I really want a two tuner two HDTV unit (HD DVR, of course). But I suppose that would take an HDMI cable rather than just a coax (because of HDCP). So I doubt we'll see anything like that in the next few years. I'm not sure what the length limit is on HDMI, but that's one expensive cable, with connectors you won't fish thru walls.
My guess is a small reduction in the ViP series prices, both purchase and lease. I think 2007 will see Dish gear up to speed up replacing the non-MPEG-4, non-8PSK receivers. And Dish Online will help them do it.
Next time my 721 dies (I'm on #6), if they offer a good upgrade deal to an HD DVR, I'll take it- even though I'll lose my "no DVR fee" grandfathered status.