Facebook Places not only lets you "check in" to various locations (a la Foursquare or Gowalla) but it allows your friends to check you in as well, which could be a little creepy. Luckily for those of us who prefer to keep where we are private, our good friend Phil Nickinson from Android Central tells us how to "just. stop. it.":
You can disable that "feature" now by going into your privacy settings. Hit the "customize" link, scroll down to the "things other share" section, and disable the "Friends can check me into places" feature."
Fortunately, the first time anyone tries to check you in you'll get an email notification, but if you prefer to do your own dang checking in, thank you very much, follow Phil's advice up top.