The NY Times has a very flattering piece on mobile-social-local gaming network Foursquare:

Just seven months old with about 60,000 users so far, Foursquare is still getting off the ground — especially when compared with supersize services like Facebook and Twitter, which have millions of members. But that underground status is part of Foursquare’s appeal, its fans say. It is not yet cluttered with celebrities, nosy mothers-in-law or annoying co-workers.

It's striking to see a 36-year-old quoted in the article praising the game/site/network:

“On Twitter, there are more than 3,000 people that follow me, and Facebook is more of a business community now,” said Annie Heckenberger, 36, who works at an advertising agency in Philadelphia. “Foursquare is more of the people that I actually hang out with and want to socialize with.”

My guess is that the quoted individual is single and has plenty of time on her hands. That's my thesis about who Foursquare appeals to; it's game-like nature makes it engaging but limits its mainstream appeal. Perhaps I'll be proven totally wrong. In the beginning I was a Twitter detractor.

In a related vein, Loopt has launched a new service called Loopt Mix, which is effectively a dating app with push notifications. There's substantial reason to believe that this is the future of Loopt and they've decided to embrace the way many people were already using the app: for hooking up.