I finally dove in and tried Foursquare. For a few months I tried remembering to check in everywhere I went. Once or twice, a coupon came through and I saves a few bucks. Ultimately, it was about maintaining connection with friends. However, few friends where active and fewer still significantly engaged. Additionally, becoming "friends" with a true stranger was quite uncomfortable; even for me (who is quite comfortable being public facing). The graph of Foursquare activity is quite intimate.
Summing up: keeping up with check-ins always felt tedious. There were a few fun exchanges with friends, but mostly nothing. For me, the experience was really devoid of value. I pretty much have abandoned the platform.
I'd love to heat what you think. Live the thing, hate it, think I was crazy to even try it? Drop a comment and let me know.