Today Microsoft has released the Beta for BizTalk Server 2009 to the public.
It is available on Microsoft’s Connect site at https://connect.microsoft.com/site/sitehome.aspx?SiteID=218
This beta will be community supported though the Microsoft TechNet forums here.
Some of the key enhancements to BizTalk 2009 is support for the latest Microsoft offerings (including Windows 2008, Visual Studios 2008 SP1, .Net 3.5 SP1, SQL 2008, and TFS), support for RFID Mobile, and new LOB Adapters (including a new SQL Adapter).
A new release of the Enterprise Service Bus Guidance is available on CodePlex (http://www.codeplex.com/esb).