Alexander Torone did a great job showing an overview of the Architects role for Visual Studio Team System (DEV365). The best part is you can query an existing infrastructure and pull in a ton of configuration information. Then the various designers will tell you if something in your application conflicts with the infrastructure settings.
And all of the designers are linked to the code. For example, Alex decided to change the name of one of his web services on the diagram and the tool changed everything: the client code, the service code, and the diagrams. It was like refactoring for web services.
Read: TechEd 2005: Visual Studio Team Edition for Architects