it almost feels like MS is straddling this line where they are moving into a "generation-less" business model, but they still have to play by some of the old rules re: physical releases. SD in theory is supposed to alliviate all of that, as you just buy the game and it knows which version is best for your hardware, but you can't do that via physical releases and via third party games when those publishing partners don't want to play ball. I doubt this will be much of an issue beyond launch, as developers and consumers move more and more onto the new systems, but its growing pains.