For months, the Bing Maps site has been showing off what are essentially embedded mashups. You can search nearby tweets, FourSquare check-ins and other content from partners. Until now, it was merely a showcase of apps either written internally or by a company that Microsoft had blessed. Now, you have the opportunity to get your mashup included on Bing's map.
It may seem like lately geo APIs and mashups are getting a lot of coverage here on ProgrammableWeb, and for due reason: the geo API providers have been busy. From the release of v3 of the Google Maps API to the release of Yahoo!'s Placemaker "geo-enrichment" platform, there has been a lot of activity on the mapping front in the last few weeks.