I got this off the Ad Age site.  Its not qualitative but it is cool.  http://adage.com/digitalnext/post.php?article_id=134330

 

Google Takes Social Networking on the Road

Maps App Lets You Share Your Location with Friends

Google Latitude
Google Latitude

Google today announced yet another addition, called Latitude, to its mobile maps service. Latitude enables you to share your location with your friends, and see where your friends are (or at least where they want you to “think” they are). Through Latitude, you are able to connect with friends by sending them a text, chatting via Google talk or even getting directions to your friend’s location. It works on any phone that can run Google Maps My Location.