http://blogs.msdn.com/silverlightws/archive/2009/07/09/adoption-of-wcf-technologies-in-silverlight-2-applications-on-the-web.aspxIf you are interested in what communication and serialization technologies are being used by others in Silverlight 2 applications, check out the post at http://tomasz.janczuk.org/2009/07/adoption-of-wcf-technologies-in.html . It is a summary of a researchen-USCommunityServer 2.1 SP1 (Build: 61025.2)