Read this book review by Matt Serbinski at Matt's Blog
If you are building applications that could use a dashboard then I would recommend taking a look at the PacktPub book “Microsoft Silverlight 5: Building Rich Enterprise Dashboards”. The book focuses on using Silverlight 5 to construct various dashboards and provides guidelines on how to achieve this from start to finish. Along the way are useful tips and tricks and gotchas that can be found when dealing with the various aspects of building a dashboard.