Last week I did an interview on a San Diego news program about issues with many cameras and smart phones in particular embedding very accurate location information in your pictures. If your camera (smart phone or whatever) has GPS, then the EXIF meta data in the picture will contain your location to within about 20 feet. This can be disabled, but is typically on by default. While this can be useful when you are trying to sort and organize the pictures on your computer, the risk shows up when you start to share the pictures. By combining date and time information in the pictures I can tell if they are recent. If you are on vacation and posting on the road, an attacker can tell that you are away from home and your home probably unguarded. Pictures of your home and family can provide the exact location of your house as well.
The good news is that major sites for sharing pictures like Facebook and Flickr seem to strip out that information from the photos. It is unclear if that is intentional or just a byproduct of how they are processing and displaying the images. In any case, the data is certainly available to the sites themselves.
I strongly encourage everyone to download an EXIF editor to be able to strip this information from pictures before uploading, and to turn off location tracking in their cameras and mobile phone photo applications to prevent the capture of that information in the first place.