What is Facebook Places?
Facebook Places, a smart phone application that allows users to "check in" to let their Facebook friends know where they are currently located. It's a function similar to what apps such as Foursquare and Gowalla. You can also leave comments and tips for friends to see. If you like a particular dish at a restaurant, or had bad service there, you can post that info with your check-in and notify your friends.
Broadcasting your current location allows a potential predator to know where you are currently located. These programs also track where you frequently visit, which a potential predator can use to harm you. Lastly, announcing you are away from your home may put your property at risk. If you do plan on using this type of social networking, it is important to use privacy controls to restrict who see’s your “check-ins,” keeping in mind the potential that your location may not stay private.
Even if you do not use Facebook Place it is possible for a friend to check you in if they utilize the service. For more information on managing Facebook Places and disabling the service please read - How do I disable Facebook Places on my account.