Recently I have been coding some stuff using MapQuest rather than Google Maps. This was mainly spurned by the fact that Google Maps is no longer free – however of course we are talking about more than 25,000 impressions per day, so it is still free for most small website owners.
Actually using the MapQuest SDK isn’t too bad, it has lots of examples and is fairly powerful. Of course the Javascript developer kit is the most useful see http://developer.mapquest.com/web/documentation/sdk/javascript/v7.0 and has plenty of common examples.
Mapquest has both an Licensed Data and Open Data access, so of course the open data is the free service.
Google Maps of course has Street View which is something no one else has, but apart from that MapQuest is just as neat.
Have you used MapQuest or both MapQuest & Google Maps. What do you think?