I am waiting (patiently) for May 1st to arrive so that Microsoft will ship my copy of BizTalk Server 2006. I am excited to start using the product and learn more about it. From what I have been reading so far, it seems to be a great improvement over the previous version (BizTalk 2004) with much better connectivity to data sources and easier setup on machines.
I have been looking for some useful information regarding the details of using BizTalk, but most of the info I have seen relates to the same generalized comments about it being better and coming soon.
One good source of info I found today was the MSDN documentation page for BizTalk 2006. Here.
The developer's reference can be found here.
Matt Hall's blog documents and answers some situations that could cause someone to lose some sleep. A good reference for anyone getting started with BizTalk 2006. Read Matt's blog here.
Here is Top-XML's list of BizTalk 2006 related blog entries.
I'll add more resources as I find them.
Ron