In this video I will show you how to upgrade or install TFS build service 11 beta on a separate build server, actually the build server machine is already has TFS build service 2010. TFS 2010 build service can coexist with TFS 11 beta build service and everyone will support it's TFSx server. If we building Windows 8 Project, the build server must be on Windows 8 machine, this is for now and for the beta, in Microsoft, they didn't know if this could change or not.
For more information on the whole old environment, you can see TFS 2010 Enterprise Video Guide on CodePlex http://tfs10enterprise.codeplex.com/