I'd like to draw the attention to a whitepaper by David Chappell – not a long one, being comprehensive, can be easily cited (like cloud platform is "kind of platform lets developers write applications that run in the cloud, or use services provided from the cloud, or both" ) – so good for enterprise consumption as well 🙂 It provides context for Microsoft Software Plus Sevices (S+S) strategy by explaining the rationale for what an operating system provides: a foundation, infrastructure services, and application services. And how a cloud platform applications compare with on-premises applications. He explains how the two application types work together. In addition, he breaks down each of the pieces that are needed for a complete cloud platform, including storage, identity, search, mapping, and integration.