I'm an over-sharer, sure. But I have happily drawn the line at FourSquare. I don't find it to be any more useful than Facebook or Twitter or any other social network. If the site and application have any notable uses that make life easier, better, or more interesting, then I have unfortunately missed that marketing message.
However, FartSquare here is something that I can happily get behind (though I'd prefer to get ahead of it and then away from it).
Plus, it'll be a lot easier to blame the blast you just passed on someone else if you can pull out a heatmap and prove it with faulty geo-location information.