Maps / Locations for listings

Hi,

Could someone please explain how the Maps / Location Settings work.

I created a test listing and in the box to enter the post code / location for the map nothing actually happens.

When I log into the admin area to set the address manually in the Map location setting still nothing happens.

I have API Credentials Key set for Maps JavaScript API from the google API library, is it a different API I should be using?

Please advise as this does not seem to work