We recently released the Bing Maps WPF Control Beta. See the official announcements at the Bing Maps Community Blog and the Microsoft Surface Blog in case you missed it.
The Bing Maps WPF Control allows you to build Bing Maps applications using managed code for Windows Presentation Foundation (WPF) applications. The interface is very similar to the Bing Maps Silverlight Control. It has multi-touch support built-in with rotation, translation, and scaling, and is designed to work with the Microsoft Surface.
The Bing Maps WPF Control Beta can be downloaded from the Microsoft Download Center. This is a Beta release, so try it out and let us know if you have any feedback or suggestions!