This one is new but seems to be on the way to what we are talking about: http://www.recargo.com/
I got the skinny from someone there and liked what I heard and went ahead and registered. Here is some of what I learned.
Recargo is more wiki like. Charging sites can be added or modified (including adding photos) by registered users. Each site has a change history so anyone can see what happened and when (and administrators can "rewind" if necessary).
I see an Iphone app in the future.