If you haven't ordered this book for your technical library yet, don't wait another minute! It's quite probably the best overall introduction and technical overview to BizTalk Server I've read to date and the current BTS2004 product documentation could take a few pointers from this book on how to explain complex subject matter simply and concisely. Each chapter builds upon the previous chapters and the explanations of “why” BTS2004 does what it does are excellent. It's a great combination of general information and deep technical insight into each relevant area of BizTalk Server 2004 from developing basic schemas, through the use of complex orchestrations and even to health and activity tracking. It's a “must read” for any user / developer / implementor of BizTalk Server 2004!
Many thanks to the authors for a well written book.
You can find it at Amazon.com by following this link: BizTalk Server 2004 Unleashed