I recently had the opportunity to get some hands-on experience with Silverlight 4 in Visual Studio 2010.

When you start a new Silverlight 4 project, you’re asked which version of Silverlight you want to target – 3 or 4. Seeing as version 4 is the latest, I opted for that, only to get a prompt to download this update. This installs not only the Silverlight 4 tools for Visual Studio, but also a new version of the WCF RIA Services library.

WCF RIA Services simplifies traditional n-tier development by bringing together ASP.NET and Silverlight using Windows Communication Foundation (WCF). WCF provides a pattern to allow you to write application logic that runs on the middle-tier that controls access to data and services.

It also provides a rich framework for common business application development scenarios such as validation, authentication and user roles.

After installing the update, you get two new Silverlight project templates that showcase the new RIA Services functionality:

• Silverlight Navigation Application
• Silverlight Business Application

The Silverlight Navigation Application template is interesting because it also demonstrates the new navigation framework in Silverlight 4. This allows you to create Silverlight pages that are associated with the browser’s forward and back buttons, something which had been either difficult or impossible to implement in previous versions.

All in all, Silverlight 4 represents a major step forward and brings a compelling set of new capabilities to the line-of-business application developer.