Hmmm... I'm virtually certain that you can build
a Google map, but I'm not sure if it can do it automatically. That is, if someone submits a photo and says where it was taken, you could then enter that info and add it to your Google map. They might be able to do this too.
Yep, others can collaborate on it (that's new evidently):
Collaborating with others
Once you have created a map, you can invite individuals or anyone to collaborate on editing your map. To do this:
1.) Create or edit a map.
2.) Click Collaborate in the left panel. A dialog box appears.
3.) Enter or choose the following:
......Invite persons as collaborators - Enter the email address(s) of anyone you want to collaborate on your map.
......Message - Type the message you want to appear in the invitation to your collaborators
......Collaborators may invite others - Check this to allow your collaborators to allow other collaborators
......Allow anyone to edit this map - Check this to enable any Google Maps users to edit your map
......Collaborators - You can remove any or all collaborators
4.) Click OK. Google Maps sends an invitation to any collaborators you specified.
GPS stuff must come into this too but I couldn't tell you how. (I know that photos taken with many smartphones and some regular phones have GPS info imbedded in them.)