I admit that at first I really didn't like the LinqDataSource, it has it own particularities that with the next iteration might be removed. Also, I thought it didn't find related table data (so wrong!).  But that was more down to trusting Visual Studio to bind the correct details for those (quick and nasty) long thought out selectable gridview to detailview scenarios.

Check out this article by Scott Guthrie, it covers more of the LinqDatasource

http://aspalliance.com/1427_LINQ_to_SQL_Part_5__Binding_UI_using_the_ASPLinqDataSource_Control.1

Article also some basic validation classes