Nearly three years after first releasing Map Maker, Google is finally ready to let its users edit and add to the map of the United States.

Google Map Maker is a parallel version of Google Maps that accepts user contributions and map edits. When approved by moderators, edits are published to Google Maps and are pushed live to all users.

The Map Maker tool has been used in 183 countries and regions around the world, and users have been actively adding the next level of detail — roads, universities, bike paths, pools and the like — to their towns. In 2008, roughly 15% of the world's population had online maps of their neighborhoods via Google Maps. Today, that percentage has jumped to 30% thanks to user contributions via Google Map Maker.

Tuesday, Google is making the entire United States map available for editing. The three-year wait, explains technology lead Lalitesh Katragadda, was due to two primary factors. Google chose to first make map editing available in parts of the world that needed detailed maps. The company also wanted to ensure its moderation and editing processes could scale to meet higher demand. After all, he explains, the live version of Google Maps in the U.S. sees millions of visitors daily.

The processing of editing the U.S. map is not without its checks and balances. Anyone Google user can sign in and zoom in to a region to add a map point or draw an entity — a newly constructed swimming pool, for instance. Once an edit is saved, it is reviewed by a moderator and posted to the live version of Google Maps within seconds upon approval.

Google employs a hybrid moderation system to ensure the accuracy and quality of Maps edits. There's a small in-house moderation team, but most of the moderation is managed by power Map Maker users who have graduated to become a part of the moderating community. "Users are best served by having complete details," says Katragadda. "The only way to get there is to have users doing it."

Google is also adding a few new features to Map Maker. Beginning Tuesday, Map Maker will integrate with Street View so users can use imagery to help guide their edits. Plus, there's now additional advanced search options.

Now that Google is giving us all the ability to become editors of the map of the United States, one can only hope that we wield our new digital cartography powers wisely.