Your local newspaper probably uses maps on its site. If it doesn't, it will soon. As newspapers look online for readership (and thus, revenue), they look for new ways to show information related to the places they cover.
Is there any question map mashups have gone serious? How about billions of dollars serious? The U.S. website Recovery.gov was built to make transparent the use of economic stimulus money. Now you can track every dollar on a map.
When looking for a place to live, the surrounding area matters. Knowing if the property has easy walking access to shops, places of interest or public transport can definitely sway a buyer's purchasing decisions. Walk Score is a service that measures walkability within specific locations and also provides neighbourhood maps to the real estate industry. Walk Score's Travel Time API makes this functionality available to be easily integrated with other applications.