When user moves around in map view, listings update

The limitation on the number of listings that appear in the map view makes it not all that useful. If a user wants to see other listings, they are unable to see directly from the map view. They have to go back and take some action with the navigation. Seems like a directory app should allow people to be able to move around a map and find things easier. Is it possible to have the map area refresh with new business listings as a user moves around within it?