"BizTalkUG is a community of people who are interested in BizTalk Server technologies and how they can utilize it. BizTalkUG.com provides the single largest independent resource for Microsoft BizTalk Server related technologies. It is one of the first in a series of sites devoted to news, features, information, and code related to one particular technology."
BizTalk.org provides additional resources in support of Microsoft's BizTalk XML initiative. Registration is required to access any of the resources which include an XML objects library, community message board, and articles and information on Microsoft's BizTalk 2000 server product line.