Since few days i have been struggling to bind a gridview from a simple WCF async call.
Following article look promising…

http://blogs.telerik.com/vladimirenchev/posts/09-10-16/how_to_silverlight_grid_hierarchy_load_on_demand_using_mvvm_and_ria_services.aspx

I conclude binding is not simple traditional databind() method call from gridview if you don’t know howto ;)

Thanks,

Suresh