One of the most tricky aspects of developing BizTalk applications can be the performance tuning and optimization phase. A great new whitepaper has just been released to MSDN that has extremely deep and thorough coverage on how to configure, install and tune the a BizTalk database tier. This is a must have paper for anyone dealing with high load, high performance BizTalk applications
http://msdn2.microsoft.com/en-us/library/bb743398.aspx
Great work done by John B. Brockmeyer and team.
Cheers and keep on BizTalking