When the icon is passed over, information appears in the pop-up window. If the link is followed by a user on the Mapplet, "you receive a share of the revenue," giving Web site developers another way to make money for their sites. (...)
Users would be able to set a limit on the number of sponsored ads on their customized map and also turn the feature off.
Google Maps shows both ads that send you to a website and ads placed on the map, but there aren't too many ads from the second category.
