Actually Microsoft has had this for a long time. They orginally created this for there MapPoint Web Service product but it regularly used with Bing Maps. There is site called the Customer service Site were you can upload xml, delimited, and excel files. You can then use MapPoint to retrieve this data and import it into Bing Maps. Here is an article on how to set this up:
http://msdn.microsoft.com/en-us/library/cc316940.aspx Aside from searching for locations by distance you can also search for locations along a route, properties, or id.
Windows Live Developer MVP - http://rbrundritt.spaces.live.com
