Want to know Microsoft's support policy for operating systems? Microsoft has published the levels of support for a period of 7 years from general availability. This is a pretty good example of how one does a roadmap. The FAQ states: The Windows Desktop Product Life-Cycle Policy is designed to establish a clear and predictable policy for product support timelines and license availability, to assist customers and partners with managing their support needs, product planning and information technology planning within their organizations based on knowledge of the support timelines for Microsoft products. Search their web site for Product Life-Cycle Policies.