Silverlight 4 RC - Native automation (COM interop)

API changes in the naming of the native integration (COM interop) feature for trusted applications. Before:

   1: dynamic excel = ComAutomationFactory.CreateObject("Excel.Application");

After:

   1: dynamic excel = AutomationFactory.CreateObject("Excel.Application");

Simple, but will catch you in a recompile :-). You can view a video on using native integration here.

Source : http://timheuer.com/blog/archive/2010/03/15/whats-new-in-silverlight-4-rc-mix10.aspx