Few months back, I wrote one article on Integrating Bing Maps in Silverlight Application. Today on the same base I am putting my thoughts for Bing Maps on Windows Phone 7 in a very short demo. The way you integrate your Bing Maps in Silverlight Application and over here is almost same since platform for both is Silverlight. You need Key for Bing Maps and API in place so as to make things easy for you, You can refer my old article here.
For Windows Phone 7, Make sure you add reference to Microsoft.Phone.Controls.Maps like this :
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