In our (internal) implementation there are a lot of differences. But you shouldn’t care about that.
In the API that you use, we have tried to minimize the differences.
If you compare GoSilverlightDemo with GoWpfDemo, you’ll see that the *.CS files are identical. There is a little bit of #if used, but it’s negligible.
In fact, if you are using Silverlight 4, there could be very few differences in the XAML too. However, our Silverlight samples were designed to work in both Silverlight 3 and Silverlight 4, so we couldn’t use a lot of the XAML improvements (fixes!?) that went into Silverlight 4. Hence there are more differences between the GoSilverlightDemo and GoWpfDemo XAML files than there really needs to be.