ZDNet Asia has an article about the lag time in updating street data in GPS units.  The article cites Ed Parsons, Google’s geospatial technologist, explaining, “the reason users encounter inaccurate road layouts and landmark placements on their GPS devices is that it takes a long time getting updated maps to users.  From the mapping of roads to getting the maps updated and onto distribution channels such as garages, people can expect their maps to be over two years old, even on new devices.” (seen via Mapperz)

Read more: GPS device maps typically two years old