Christian Belady (Our Principal Power and Cooling Architect) and David Gauthier (One of our Data Center Engineering teams) put a post up answering some of the many questions we have been getting around our Generation 4 Approach. Its some good additional primer information and addresses some of the recurring themes we are getting in mail.
Check out their joint blog at : http://blogs.technet.com/msdatacenters/
There is also a good video interview of them here.
/Mm