I found this article:
http://tech.yahoo.com/news/ap/us_tec_blu_christmas interesting relative to the debate within this thread. There are points made to support both sides, so if you pick and choose- as is being done within this thread- you can draw out of this support for both visions.
My perspective cuts down the middle: deliver an

TV largely as is, with 1080p hardware, a few "normal" (open) expansion ports, an "open" software platform (iphone like) SDK, plus app store. Apple could deliver this one without having to up the price, still get the Apple margin, and leave a lot of buyer wishes to third parties.
As such, my perception is that Apple needs to do what it needs to do to get this box entrenched in the mass market's living rooms. People will buy only so many set-top boxes, and the guy with 1080p BD player, and a DVR, etc is not going to be very motivated to go buy a 720p

TV which, to approximate the DVR experience will then involve having to rebuy (some) shows already flowing into his home.
Give the market what it wants (through third party add ons if necessary) then obsolete the BD and DVR functions over time as we move toward the "vision" of "download everything from iTunes". Don't give the market what it wants, and Apple doesn't entrench this box in mass market living rooms, and someone else will win this battle. From my perspective, here's key excerpts from that article...
"
There are now Blu-ray players in nearly 12 million U.S. homes"
and
"
Until now, the pace of adoption for Blu-ray has matched what DVD had when it pushed aside video cassettes more than a decade ago"
I think its safe to assume that there are not 12 million

TV's in U.S. homes.
The second quote presents the opportunity for Apple: follow the model of what made DVD players fly into homes (which is not solely deliver lower quality picture than standards that are readily available), entrench, then ride the wave that follows. BD is struggling to stick with the pace at which DVD players flowed into mass market homes, but certainly not because

TVs "as is" are eating their lunch. Thus there is a hunger for a great "next gen" alternative which a next-gen

TV could fulfill.
If I was Apple, I would kill 2 or 3 birds with one stone, by delivering a 1080p device that can also (optionally) be a BD player and a DVR (if users wanted to add those on). Keep the price about where it is, and Apple would basically be giving the market the choice of buying individual boxes or buying one box with lots of customizing feature options. It is easy to imagine that I'd sell tons of these next-gen 1080p

TVs, entrench in mass market (not just Apple fanatic) homes, then leverage the convenience of deep library of content available via iTunes to eventually obsolete the BD and DVR add-on pieces (much like home AV equipment like the use of VCR's & Laser Disc players were eventually phased out by their buyers, as more convenient and/or better quality options came along).
Whatever boxes "fill" the stack next to the mass market's HDTVs are the boxes through which video content can be subsequently sold or rented. If Apple doesn't make it's box so appealing that the mass market deems it a "must have" addition to their AV stacks, there is no iTunes rental revenues from boxes that aren't in those homes.