The best replacement for bing maps is google maps.

The best alternatives to bing maps are rated as following:
★★★★★  google maps
★★  google earth
★  nokia here
★  esri
★  mapquest
★  mappoint
  google maps which is better
  nokia drive
  yahoo maps

Your alternative for bing maps is not listed? Suggest!
Speaking about bing maps, one probably shouldn't forget about leaflet.

Other search terms related to bing maps and their ratings are:
★★★★★ leaflet
★★ openlayers
★ arcgis
You have in mind a companion for bing maps and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of bing maps in all years. Click on graph for more.
bing maps
google maps
google earth