Related tables and relationship classes are critical to retrieving useful data in a GIS. There are many times when a "field join" simply will not do, such as when you have a one to many relationship. Please add this functionality to the Silverlight viewer. I'm still searching for a replacement for the .NET ArcGIS Server Manager. So far, neither Silverlight or Flex meets our needs which means we cannot upgrade to version 10.1 when it comes out.