Foursquare and social trends
It’s unclear from the Foursquare check-ins themselves how old users are…
Would be a great option to provide for anonymous data mining. Potential is there for a huge amount of information on social trends and topics. I bet Facebook already has this information though, which would be acquiring the likes of a Foursquare could be beneficial since their user base is exponentially greater. Yep, Facebook has check-ins - but Foursquare is more fun.