The fact that XB1 and win8PC cross platform is not the central focal point of this new console generation is exactly why it is going to fail unless they figure it out quickly. I already have a nice game rig at home, and have no interest for them to sell me almost the same hardware, with the same OS, but with less features and capability. But what I would not mind is that if I wanted to play multiplayer games with my xbox friends from my PC would be the requirements of having and using an xbox controller, kinnect, and a gold membership. I already have an xbox controller, and will probably get an XB1 controller for the PC when available because they are just nice controllers. The addition of Kinnect would only add an extra $100-150.
I would much rather spend that kind of money than to buy a $4-500 console that I am only going to use for 2-3 games over it's 8 year lifespan as the vast bulk of my gaming will be on the PC.