"Citizen cartographers" help Google map North Korea

I have been aware for several years now of crowd-sourcing efforts to map North Korea using Google Earth. That effort is led by Curtis Melvin, who publishes a website called North Korea Economy Watch and who collaborated with the Johns Hopkins School of Advanced International Studies on a digital atlas of North Korea.
However, I was not aware as reported by the Wall Street Journal and other media outlets around the world,  Google has published a detailed map of North Korea on its Google Maps program, after years of a crowd-sourcing effort using its Map-maker program. The article reported that "On Tuesday, the company revised its Google Maps application to add information for North Korea—from naming streets to marking the outlines of prison camps—beginning to flesh out a national map that has been largely unannotated since Google started providing maps online and for mobile devices eight years ago."
The Map-maker program has already started to attract both serious additions to what we know about North Korea, and also humorous comments from web surfers around the world who obviously haven't much real interest in the country.  The problem facing Google's map-maker program, as with other crowd-sourcing efforts, is how to distinguish credible, sincere efforts to provide information from the equivalent of social media spam.