Biztalk and windows workflow

A lot has been said regarding Biztalk server and Windows worflow foundation, here are some references that might come handy:

• BizTalk Server 2004/2006 and Windows Workflow Foundation by Brian Loesgen
• Windows Workflow Foundation vs BizTalk Server by Lamont Harrington
• Windows Workflow Foundation - Where does BizTalk fit in? by Darren Jefford
• Introducing Microsoft Windows Workflow Foundation: An Early Look by David Chappell