So I’ve run into the addictive nature that is geotagging my Flickr pictures. Geotagging allows you to add a piece of information to the picture so that it knows where the picture was taken. It then takes those locaitons and plops them on a map. You can check out the 30 or so pictures I have geotagged here:
http://flickr.com/photos/penut/map/
I’ll have every new iPhone picture automatically geotagged but as for the DSLR pictures I’ll have to do those manually 
