1. The document discusses the evolution of business models for IT infrastructure from proprietary systems within individual companies to more open standards and shared infrastructure leveraging the internet. 2. It describes new service models like client-server computing, web services, and on-demand/utility computing which allow flexible provisioning of computing resources on a needs basis. 3. Managing diverse IT infrastructures requires considerations around outsourcing non-core functions, developing service level agreements, managing legacy systems, and aligning infrastructure capabilities to business strategy through appropriate investment.