World wind is cool and has some advantages over GE, but GE has more consistent maps (WW is better in some areas if you switch to Urban area ortho, but worse in most areas), street overlays, built in Google Local search with driving directions, better bookmarking, etc. (and it is just as open a system as WW. Google encourages people to write
plug-ins, overlays, etc just like they do for Google Maps. Well maybe not "just as open", but it is somewhat open).
WW just doesn't seem as fit for a in-car Nav program (even if the map data is free).
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