This really doesn't look like one of those "if you squint, virtually any web app written in the last 10 years could infringe it" kind of patents. It looks like a patent on Foursquare.
I agree, the patent situation is a mess. And this is probably a terrible patent encumbered by all sorts of prior art. But on paper, it's a pretty good leg to stand on.
If I've learned anything about the patent system, it's that it doesn't matter if you've been doing it since 1776- if they've got a patent on it, you better watch out.
If you personally have been doing it since 1776, you're fine. It's usually more like some obscure product by a now bankrupt company did the same thing, but neither they nor the product is currently available.
I agree, the patent situation is a mess. And this is probably a terrible patent encumbered by all sorts of prior art. But on paper, it's a pretty good leg to stand on.