This session presents an overview of how to expose data to a Silverlight application by accessing web services in the enterprise. We will cover a spectrum of options spanning from the client HTTP stack to WCF to WCF Data Services. We will first show off the functionality of the new client HTTP stack with respect to HTTP verbs, headers, responses, and authentication in the context of the REST protocol. On the WCF front we will walk through a demonstration of how to use Silverlight with a new WCF message pattern …

In this presentation filmed during QCon London 2008, Christian Weyer, co-founder of thinktecture, explains how to create distributed systems using SOAP or REST on top of Windows Communication Foundation (WCF) or Windows Workflow Foundation (WWF).
http://www.infoq.com/presentations/SOAP-REST-Christian-Weyer