I actually found this weeks ago; but keep forgetting to write it up.
It just makes so much sense. Users add descriptors of places to a satellite map. Other users can vote whether they agree with the description or not, they can also add to it or correct it. When enough people have voted that they agree, the description becomes permanent.
So you can label parks and schools, grocery stores and pharmacies, churches and landmarks, graveyards and landmarks. I can see when this hits a certain critical mass it could be very useful indeed.
Warning: you can lose hours playing with this.
I got the link from Melissa Wiley who in planning a cross-country move had already scoped out her new neighborhood on the other coast. How cool is that.