The experience: a frenzy of sharing entertaining photos and having fun anytime, anywhere, with anyone.
The reality: a classier, more respectable and 'innocent' rival to Grindr.
The money: push advert pics into the localized photo streams, even making them geographically contextual, exposing them to an already captive audience, who may even react and start talking about it (the advertised product/service) on the spot.
Actually, have to admit, I really like the idea.