Here is a great document that describes how to implement high availability for BizTalk Server components and dependencies using Windows Server Clustering technology. How to improve Fault Tolerance in BizTalk Server by Using a Windows Server 2008 failover cluster or Windows Server 2003 server cluster
Here are some videos demonstrating how to use the WCF support in BizTalk. This Windows Communication Foundation (WCF) video demonstrates using the BizTalk WCF Service Publishing Wizard. This Windows Communication Foundation (WCF) video demonstrates using the BizTalk WCF Service Consuming Wizard. This Windows Communication Foundation (WCF) video examines how to configure a BizTalk receive location using the WCF-Custom adapter...