A new WCF adapter whitepaper entitled “Modifying Messages with the WCF Adapters” is now available for download. You can get the Word version of the whitepaper at http://download.microsoft.com/download/c/f/b/cfbcd6ad-5454-4c23-85d2-0cc3d7627015/WCFModifyingMessages.doc. Alternatively, it's location in the MSDN library can be located at http://msdn.microsoft.com/en-us/library/cc950532.aspx.
Here is a summary of its content. Enjoy!
The Windows Communication Foundation (WCF) adapters enable you to modify both incoming BizTalk® messages and outgoing WCF messages. You can use an XPath expression to specify what part of an incoming WCF message to use as the source of the BizTalk message body, and you can use an XML template to modify the content of an outbound WCF message body.