The article was saying MS is working with Intel on Windows 9 with the goal of making it the first 128bit OS... and Windows 10 being the first 256bit OS... I'll see if I can dig up that article again.
I've built servers with up to 256 GB RAM. For the sake of estimates, let's say 1 TB RAM is about tops right now. That's 2^40. If we extrapolate with Moore's law, we'll max out 64-bits (2^64) in about 36 years. (Realistically it's going to be a lot longer than that) There's no way MS is going to support Win9 40 years from now. There's no 128-bit hardware in the works, so there's no point in designing 128-bit software for the foreseeable future.
256-bit computing will likely never happen.