This document discusses the realities and opportunities of software as a service (SaaS) and cloud computing. It notes that while SaaS is an understood concept, cloud computing is still newer and murkier. It highlights how SaaS has created billions in market value for winners like Salesforce.com. It also discusses how the cloud is shifting IT infrastructure away from on-premise data centers and towards virtualized third-party providers, which has implications for both customers and equipment vendors. The document advocates investing to win in specific niches within SaaS and cloud computing.