Another problem that the author neglects to mention is that Meetro didn't really seem to solve any specific problem.

Foursquare is so successful for two reasons. It's a game, so people want to check in and leave their mark (solving the persistence problem he mentions). They're solving a problem by providing entertainment. I'm not seeing this as much in Meetro. Second, everybody has smart phones now. Foursquare succeeds where Dodgeball fails because anybody can participate, with almost no effort.

Very cool blog post from 2008!

Right there at the very end in point #3 he ponders the option that just turned into a $80-100m valuation. He was thinking of the idea but didn't have the social proof from the cool kids.

Not being able to pivot to the right model and timeliness seem to be what went wrong.