We've already told you how to disable (or enable) the feature in Facebook Places which allows other users to tag you at a location. Do this now! If you don't take any action, you're left in a confusing privacy limbo.

There are three situations a Facebook user faces, when it comes to the "friends can check me in" feature of Facebook's new location-broadcasting service. 1) You've enabled it. Any of your friends can check you into a place, as they would tag you in a picture or status update. 2) You've disabled it. Only you can check into a location. 3) You haven't bothered to change your privacy settings; you've neither allowed nor disallowed your friends to tag you. This gets confusing. TechCrunch explains what happens if users continue to coast along in situation three:

As soon as they get tagged for the first time, they'll get an email and a prompt on Facebook itself asking them if they'd like to allow their friends to tag them at Places in the future. Accepting this will allow any of your friends to tag you unless you go into your privacy settings and cancel it (see Option one).But even if you hit the "Not Now" button, you'll still be tagged in the relevant Places update. In fact, you'll still be tagged even if you haven't even seen the prompt asking you to approve Places tags. Facebook treats this as if you were tagged in a basic status update so it will show up on your Wall and your friends' News Feeds - you just aren't associated with whatever Place your friend was tagging you into (i.e. if your friend visits the venue's Place page, they won't see that you've previously checked in there).The logic here is that your friends could manually tag you in a normal status update anyway.

In short, if you're lazy and haven't adjusted your privacy settings, your friends can sort of tag you in a Places check in even if you decline to allow it when Facebook prompts you. Sure, the tag will only behave as a regular status update. ("John and Roger are at Brentwood Mall shopping for Star Wars memorabilia.") But these status updates will always broadcast your location. Get it? No? Well then go change your damn privacy settings, already.[TechCrunch]