We recently updated the Bing Maps AJAX Control v7 a week ago with some new features.  Check out the official announcement on the Bing Maps  Blog if you missed it.  Here are some details for developers of the new features in this update:

• New Bing Maps AJAX Control 7.0 interactive SDK which shows interactive samples of how to use the different features of the  Bing Maps AJAX Control v7.  The interactive SDK has code samples you can run and see the source code for and makes it very easy to try out APIs and build applications with the v7 control.
• New inertia feature which animates the map when panning the map.  This provides a nice effect especially on touch devices where you can flick the map. The useInertia and inertiaIntensity properties were added to the MapOptions.  By default  useInertia is set to true and the inertiaIntensity option is set to 0.85.  You can adjust these properties to turn off or customize the inertia effect.
• New backgroundColor property was added to the MapOptions. This allows you to modify the color behind the map imagery.
• New tileBuffer property was added to the MapOptions which allows you to customize how many buffer tiles appear outside the map view.  By default it is set to 0.  This option specifies the number of buffer tile rows to load outside the map control view boundary. This setting allows you to customize the map experience for more visual smoothness when panning.
• New fixedMapPosition property was added to the MapOptions.  This setting by default is false.  Setting this to true can improve performance of the map control when you position the map control in a div that will not be resized or moved on the page.  This primarily is for mobile web applications that may have a fixed screen size or a browser that will not resize the page.
• New dynamic module loading support for the creation of modules to add on to the v7 control.  The loadModule, registerModule, and moduleLoaded methods have been added to the Microsoft.Maps namespace for module registration and loading.  See the Module Loading methods topic in the MSDN documentation for more details.
• New GeoLocationProvider class was added with geolocation methods that make it easier to detect and display a user’s location on the map.  This feature leverages the W3C Geolocation API specification and is supported on browsers that have support for it.
• New asynchronous loading support for performance improvements on web pages that load content in parallel.  If you want to load the map control asynchronously in parallel with other items on your page, use the onscriptload parameter on the map control handler.  See the Setting Map Control Parameters topic on MSDN for more details

For more details on using the Bing Maps AJAX Control v7, see the AJAX v7 interactive SDK or Ajax v7 SDK documentation.