The top 3 things SQL DBAs need to know about BizTalk. (In order of importance)

1. BizTalk Server has its own backup story and SQL DBAs need to become fully acquainted with it. Do not assume that the normal SQL Backup tasks will adequately backup your BizTalk Server. The BizTalk 2006 documentation is comprehensive in this area. http://msdn.microsoft.com/library/default.asp?url=/library/en-us/bts06coredocs/html/82fc1af2-1389-4c79-80dc-f2df5656d201.asp
2. There are several things about the way BizTalk uses SQL Server that are unusual.
   1. http://support.microsoft.com/kb/899000/
   2. /http://support.microsoft.com/kb/912262
   3. The SQL Server Agent must be allowed to run continuously on the server hosting BizTalk databases.
3. BizTalk uses SQL Server extensively during normal operations. Try to ensure BizTalk and SQL Server are separated by as few network hops as possible.