"Also, what happened to do one thing and do it well?"This is an oft-missed point when discussing these tech services. Foursquare is a cool little product that many people find fun and interesting. It's done well, and within that context is fine.
But what's wrong with these companies earning a few hundred grand in profit and maintaining a small, stable company? Instead, VCs throw money at them like it's going out of style, and we lavish the founders with platitudes like they invented electricity or cured cancer. In that context, of course they're in trouble. It's a check-in game for crying out loud. Last I heard, they had a valuation well over half a billion dollars. Really?
So, in reality, they're not doing anything wrong. But our expectations for the next-big-thing are certainly out of whack.