wbbigtymer:
None of these scenarios or explinations begin to address why it would be only (NEW) OEMs, though. Why wouldn't it be supported by ALL digital cable ready computers (which are all OEM-only by definition)?
Ulitmately, my belief that this is the "initial" stage. It allows them to get some traction in a very controlled and tested environment where the OEM's are as culpable for it working as MS is. Again, I'll note the big boys (HP, Dell and to a lesser extent Velocity) staying on the sidelines for now.
I could foresee a time where the OEM's will be allowed to offer it to existing customers, but not from MS directly. Again, this keeps the OEM's skin (and reputation) in the game.
As far as the homebuilders (of which I am also a member), I don't really see it as an option until Windows 7. With Windows 7, you won't see any of these "Capable" systems in the run up, that was an unmitigated disaster. They will also probably publish a strict compatibility list for people who want to use the advanced Media Center features. This will cut down on the scenarios they will officially have to support.
Again, not necessarily my favorite option, but MS just can't support every possible permutation. The argument I am already hearing is "well, open source does". As someone who also has a few Linux laptops lying around, driver support can be had, but it takes a bit of work. As for the "Apple's stuff works" argument, you are actually advocating for the OEM only model, because that is what Apple is. They are the only OEM supported and they have a limited set of test scenarios to work out backwards compatibility on. It works great in their model, that's just not MS model. I don't believe that in and of itself negates the MS model though.