So, with the big announcement about the upcoming release of Windows Workflow Foundation (WWF - gotta love that acronym; I was surprised not to see Hulk Hogan here presenting), many BizTalk developers have already started asking what this means for BizTalk Server.
The simple answer is that BizTalk 2008 (or whatever the official name becomes, but not 2006) will host the workflow runtime for its orchestration capabilities and will extend workflow with all of the great things you've come to expect from BizTalk. BizTalk Server will be your enterprise solution for scalable, reliable message based integration, business process management and SOA applications and services. BizTalk will be providing MANY important features on top of the basic workflow foundation that you will want for your EAI, B2B, and SOA apps, like pipelines, adapters, management, infrastructure, security, etc. So, before you run off and say, "With WCF ("Indigo") and WWF, I can build my own BizTalk"; think twice, or maybe five times. The BizTalk team has years of experience and customer data points for building the manageability, scalability and reliability that an application of this type demands and they will continue to deliver a product that goes far beyond the capabilities of the WWF.
However, the great news is, skill sets in WWF, which will likely reach more developers, will be greatly applicable to BizTalk Server 2008 development. And, because the workflow foundation is extensible, it is likely that BizTalk developers will get their biggest wishes answered in two ways. 1) BizTalk Server 2008 will almost definitely include VS.Net debugging for orchestrations as this is already built into WWF. 2) BizTalk 2008 will easily have the ability to allow developers to create and use custom actions, and we'll have to watch for the product team to include.
All that being said, and my passion for BizTalk being obvious, WWF is hugely powerful framework on its own and will allow developers to create amazing applications while improving their productivity. The activity model will also help in the ever present goal of making reusable components. So, I'm very excited about WWF, and glad we can now talk about it publicly. Look for more information here on my blog and the Pluralsight web site for upcoming announcements related to WWF, WCF and BizTalk.