This is a very interesting tour of the main Mac lab run by Microsoft's Mac Business Unit. This is the unit at Microsoft that is made up of a lot of developers who just love the Apple Mac. They also create perhaps the best selling software for the Mac - Office Mac.
Now Mac lovers will enjoy all the pictures of Macs but I think the really interesting thing about that link is the description of the issues of running a large test lab. The writer talks about things like heat and power, backups, and how do you access hundreds of computers without having hundreds of keyboards and monitors. If you want to learn a little about what large labs are like this is the link to follow.