Here are some articles I found interesting that I've read recently:

• Workflow in Application Integration: Kevin Francis talks a bit about application integration architecture in the enterprise on the Architecture Journal 9. Despite the title, it doesn't really talk much about Workflow, but rather about the whole architectural perspective on integration.
• Commonwealth Bank of Australia CommSee Solution: An interesting look at a case study, in this case the CommSee application at the CBA. Part 1 focuses on the overall backend architecture for the application; Part 2 focuses on the front end: a Smart client Windows Forms application and Part 3 focuses on the infrastructure and development/test process.
  A few other architecture case studies can be found here.
• Building Interoperable Insurance Systems with .NET 3.0 Technologies: An interesting case study on building an insurance system based on insurance standards (ACORD), WCF and Web Services, Windows Workflow Foundation, a smart client and BizTalk Server 2006. It also appears to use "SQL Server 2006" . Some really interesting bits here...

Architecture, WCF, BizTalk Server, WF