If you have never heard of crowd sourced maps, checkout our previous blog post here or an example of a growing Philippine map in timelapse.
At Nokia world 2009, Navteq announced they will be crowdosourcing map, routing, and traffic data. Twice has a good overview. Also see a recent Google's blog entry about google's crowd sourcing strategy.
jKontherun reports that iphone users can utilize but aren't contributing to Google's arterial data. Google was quoted as saying “The Google Maps application that comes pre-installed on the iPhone can display live traffic, but Apple devices do not participate in the traffic crowdsourcing.”
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