Xbox development is already done on the PC, and without optimization or customization to the Xbox you can nearly just flip a flag to compile for the PC vs the XB, from what I understand.
MS has discussed how they are moving to more shared resources, using XNA as an intermediary. Tech from the PC, like HLSL, moves to the XB, while tools from the XB for tuning/optimization are making their way back to the PC. But at the end of the day, consoles and PCs are two different systems to target, and you will need to customize your approach. As the Xb1 gets older and older, today's PC machines outpace it hugely, and thus you can do more on a modern PC. The XBox 360, from what is publicly known, looks to be a much different beast than an x86 PC. So while you might code in similar manners, optimization/customization will become further and further apart...
PC game development is where independent game developers can really carve a space for themselves, even if a small space. The console market requires significant capital, or a contract to develop for a big company, neither of which are easy to come by, both of which have their 'masters' to pay.
-d