Visual Studio 2010 Visualization and Modeling SDK

The Visual Studio 2010 Visualization and Modeling SDK includes:

• Project templates that help developers create graphical or Form-based (Windows.Forms and WPF) designers hosted in Visual Studio for viewing and
  editing models for a custom Domain Specific Language.
  
• Project templates that help developers create extensions for the Architecture Tools in Visual Studio 2010 Ultimate
  
• MSBuild tasks that allow you to do generate textual artifact at build time for any use of T4
  
• Reference assemblies and IntelliSense documentation for the DSL tools runtime, which ships with Visual Studio 2010
  
• A migration tool helping DSL authors who were using the Visual Studio 2008 SDK to migrate their existing designers to work with Visual Studio 2010
  
• Header files containing Command IDs for the graphical designers and the architecture tools (UML designers, Layer designer)

Samples and documentation can be found here: http://archive.msdn.microsoft.com/vsvmsdk

The SDK is no longer included in the Visual Studio 2010 SDK, but does require it to be installed first. The Visualization and Modeling SDK is installed as an overlay of Visual Studio and the VSSDK. It is now a separate install so that it can updated independently