Choosing the right workflow tool for your project
Kris Horrocks and I gave a talk about this at TechEd US last year. The talk described a dozen different scenarios where you need some enterprise application integration and workflow. For each scenario we discuss different types of customer needs and whether BizTalk or WF would be a better solution. Recently Kent Brown wrote a whitepaper based on the talk which is published here:
http://msdn2.microsoft.com/en-us/library/cc303238.aspx
