I often share links and stuff on facebook and now they have a new interface for sharing links. One of the capabilities is sharing your location to all your friends.
You can add photos, ask some questions, share the link and also share your location to the rest of your social networking friends
If you do not know what am I talking about, look at the circled words, in the above picture
Why the heck do you need to tell your current location on social networking websites. In my opinion it is an intrusion of privacy and if you are afraid of everyone not knowing where you are, don't worry, they will give you a call and ask * face palms and shakes own head*