As of yesterday, developers can download the Bing Map App SDK and start building, testing and submitting applications to Bing Maps to be featured in the gallery.
To access the Bing Map App SDK, login to Microsoft Connect at http://connect.microsoft.com/bingmapapps (you’ll need a Live ID, so make sure you have one). Download the SDK which comes with a Bing Map App template and start cranking away on your project in Visual Studio (note: the Bing Maps site was upgraded to Silverlight 4 - read more about the changes to Bing Maps). Once you’ve created your application, you can test it on the site itself. That’s right! The developer sandbox is the actual site. You simply need to go to http://www.bing.com/maps/explore/?developer=1&preview=1, click the map apps button and you’ll unlock our secret map app test tool.
Along with the SDK the Bing team also published new map apps from external developers – Weather by Weatherbug and EveryScape by Everscape.
And you can also win prizes by writing your map applications (by participating in the King of Bing Maps Challenge).
Check our more details in the Bing Maps blog: http://blogs.msdn.com/controlpanel/blogs/posteditor.aspx?SelectedNavItem=NewPost&WeblogID=5193
For Bing Maps questions try using the Bing Maps forums: social.msdn.microsoft.com/.../home
If you are creating a Windows Store app then take a look at my free eBook: rbrundritt.wordpress.com/my-book