Microsoft Patterns & Practices released a downloadable PDF on CodePlex that helps Composite Application Block ( CAB ) and Smart Client Software Factory ( SCSF ) Developers understand the differences between CAB and the Composite Application Library in Prism.
Using this knowledge, developers may more easily migrate existing SCSF Applications to Prism ( i.e. Composite Application Guidance for WPF ) and/or better understand Prism using concepts releated to the Composite Application Block and Smart Client Software Factory.
The guidance is about 17 pages long and entitled-
Composite Application Guidance for Composite UI Application Block Developers
- Introduction
- Intended Audience
- Why Migrate from the Composite UI Application Block to the Composite Application Library?
- Moving from the Composite UI Application Block to the Composite Application Guidance
- Application Structure
- Application Startup
- Where did the WorkItems go?
- Workspaces and Regions
- Providing Metadata to a View
- Presentation Patterns
- Registering Services
- Wiring Views and Services Using Dependency Injection
- Event Broker
- Commands
- More Information
- Appendix
- Emulating WorkItems Using Controllers with Scoped Containers

You can download the guidance here.
Prism and Composite Application Library for WPF Tutorials