ttd,
I’m sorry but I need to say that there aren’t any documentations or resources for the differences between them. The big differences come from several reasons as following.
1. We began to develop the SilverlightEdition based on the Microsoft Silverlight 2.0, which has lots of limits in that time.
2. The EditOverlay in WebEdition is implemented by OpenLayers library, so lots of functions are very similar to it. But in SilverlightEdition, we implement by ourselves using high performance mechanism of Silverlight.
Sorry giving so inconvenience. Good news is that we will do a big change and enhancement after Microsoft Silverlight 4.0 release.
Any question please let us knows, thanks.
Johnny