I updated to new ArcGIS api for silverlight 3.0
My previous errors are now gone but a new one has presented itself....
Error 2 The project currently contains references to more than one version of ESRI.ArcGIS.Client, a direct reference to version 2.0.0.314 and an indirect reference (through 'ESRI.ArcGIS.Client.WebMap.GetMapCompletedEventArgs.Map') to version 10.1.1.0. Change the direct reference to use version 10.1.1.0 (or higher) of ESRI.ArcGIS.Client.
It points to this line of code: highlighting e.map
LayoutRoot.Children.Insert(0, e.Map)
Any thoughts?