The new feature only reveals itself to users once they have checked into a location using the Google Latitude app. Once that has happened, points are earned and the player is directed to the Leaderboard which shows the standings of the user and his Google+ friends. There is also a global Leaderboard that ranks everyone according to the number of points they have received from check-ins. The person with the most points gets a crown placed above his/her number one ranking. Unlike Foursquare, Leaderboaerd does not have a Mayor for each location.
source: AndroidWorld (translated) via Engadget