Google's Leaderboard feature in Latitude is a competitor to FourSquare.

[img]http://dl.dropbox.com/u/57456927/forum/Feb2012/latitudeleaderboard.jpg[/img]

Check out the link below for more info:

source: http://translate.google.com/translate?sl=auto&tl=en&js=n&prev=_t&hl=en&ie=UTF-8&layout=2&eotf=1&u=http%3A%2F%2Fwww.androidworld.nl%2F109985%2Fgoogle-voegt-spelelement-aan-inchecken-maps-toe%2F