I love it when best practices get incorporated into tools to help you actually follow them in an easy and intuitive way. ServiceBAT, released by the Microsoft Patterns & Practices team, seems to bring a bunch of basic principle of Service Oriented Architecture into Visual Studio with a package called the Service Baseline Architecture Toolkit (ServiceBAT) project.
Edward Bakker has a great post on his blog with demo screenshots.
The download can be found on GotDotNet. It still all very much beta!
WSCF - Schema-based Contract First Web Services by ThinkTecture is another great tool which takes a similar approach, but also improves the WSDL for your web service.