PArt 3 of my series on Prism 4 is now live on the Silverlight Show here. This one drills down into CompositeCommands and Prism pub/sub events with the EventAggregator. I show how to use CompositeCommands to hook up loosely coupled parts of the app but still have the enable/disable functionality that commands off that events do not. Then I show using Prism events to keep two loosely coupled parts of the user interface synchronized without them needing to know about each other.
Check it out!