The foundation for PerformancePoint is categorized by the acronym MAP. Monitor, Analyze and Plan are a basic iterative approach to business performance management and MS has used this approach in developing and delivering PPS.
As of RTM, there really seem to be two distinct components, with Planning standing alone and Monitoring and Analytics being merged into the Monitoring server component.
While both are based on SQL Server 2005 and Analysis Services, the structure and delivery of Planning and Monitoring are decidedly different for the initial release. Planning is delivered via an Excel Addin, with a web interface for application and user administration and a thin client for modeling and process management.
Monitoring/Analytics is tightly integrated with Sharepoint, requiring either Windows Sharepoint Services 3.0 (WSS) or Microsoft Office Sharepoint Server 2007 (MOSS).
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