Okay, so the folks at FlowingData.com pointed out Weeplaces, which is a Foursquare visualizer. Pretty cool. My map looks like this (zoom out so you at least can see Worcester and Smithfield, otherwise it just pings all over the place off map):
I also just like looking at all my Foursquare checkins on a map sometimes – if you go to foursquare.com/feeds, you can get a KML version of your checkin locations. Copy that into a Google Maps search box and add “?count=500” (or adjust it to however many checkins you have) and it’ll display a Google Map with pushpins for each checkin.