PC Pro have an article which shows that Microsoft are working towards making Windows 8 an 128-bit operating system. This leak came from a MS employ via a social networking site (which just shows you should be careful what you write!):
You can read more here.The senior researcher's profile said he was: "Working in high security department for research and development involving strategic planning for medium and longterm projects. Research & Development projects including 128-bit architecture compatibility with the Windows 8 kernel and Windows 9 project plan. Forming relationships with major partners: Intel, AMD, HP and IBM."
Morgan's LinkedIn profile has now been pulled down, but a version remains in the Google search cache.
A move to 128-bit support would be a bold move for Microsoft. Many, including PC Pro's own Jon Honeyball, were urging Microsoft to make Windows 7 64-bit only, but the company continues to offer a 32-bit version of the forthcoming OS