There have been a number of posts recently about the issues of locational privacy with the rollout of Facebook’s new Places feature. (There are other sites out there that do similar things: FourSquare is one of the better known.)
The issues with locational privacy are complicated. Some are fairly obvious (people who have stalkers or other people harassing them obviously don’t necessarily want to be found.) Some are related to pranks that can have long-lasting effects (being ‘checked in’ to a location that would look bad to your boss – even if you were nowhere near there.) And some are complex: no one really has the stats on whether burglaries happen more to people who ‘check in’ far away from home, but do you really want to trust that one?
And even if you do want some people – your closest friends, the people you’d want to tell anyway – that doesn’t mean you want to tell the whole world. If you only friend people on Facebook that you are quite close to, no problem. But if you have people friended who you’re not as close to – or maybe don’t even know very well – then you probably want to change things from the default ‘Friends Only’ setting. Here’s a great article on changing the Facebook Places privacy settings.
There’s a great article from the EFF about the issues of locational privacy (that go far beyond these kinds of ‘checking in’) sites – they also talk about the implications of transit passes, electronic toll paying devices, and other ways to match up a specific person with a specific location. The Center for Democracy and Technology also has a good article.
And finally, if you’d like a totally different way to understand some of the issues with locational privacy, I recommend Cory Doctorow’s YA novel Little Brother. You can download a copy for free from Cory’s site – or, of course, get it from your local library or bookstore.