A feature article for Computer Graphics and Applications, a publication of IEEE.
Abstract: "Consumer sites such as MapQuest, Yahoo! Maps, and Google Maps compete to improve their interfaces and data relevance to better appeal to the browsing public. But innovation in online mapping isn't limited to these household names. Sites for the public good, such as those the US government manages, provide graphical access to data buried in such sources as the US Department of Agriculture Forest Service and the decennial census. Meanwhile, community mapping sites let the public provide local details, find nearby colleagues, and organize information in ways unknown 10 years ago."