If you already haven't check out this site, it will give you a high level understanding of how you can integrate SharePoint with Silverlight. Now that the new version of silverlight is out I think it's time to integrate it into SharePoint.

http://www.ssblueprints.net/sharepoint/ 

This site has the following sample's code, video and documentation ready for download.

1. Hello Silverlight Web Parts and the SilverlightPart
2. Silverlight Navigation Controls
3. Siverlight Social Networking Web Part
4. Visual How-To center with Silverlight
5. Picture Viewer sample
6. Silverlight Custom Field Types 

Here are the sample screen shots of the silverlight controls

Custom Field Type Example 

Picture Viewer Sample

Silverlight Navigation Controls