this is more description about this extension :
This Community Interactive Map extension helps customers and visitors to contribute actively by submitting markers on a Google Map integrated in the store. The map can be loaded with different view styles and zoom in/out features. This extension will allow you to have a Community Interactive Map on your website, that means anybody can share a place to visit by using the form which include a geocoder system.
To add a place, the website's visitor just needs to click on the map where the marker needs to be, then the geocoding system will add the address,latitude and longitude into the form. You will need then to continue to fill the form, like giving the name of the selected place, optionally give your email and choose an icon image from the selected list for the marker. If the address detected is not the one you need to show, you can edit the form to change it. Then by clicking the blue button "add marker" a message displaying that an email has been sent to the website Administrator to let him validate or not the new marker added.
This is a screenshot, do not hesitate to try it, the city of Los Angeles is also in the list