Thank you for explaining. I thought you were taking a different angle entirely...

Facebook is not secure at all. Some people actually have about a thousand "close" friends on Facebook. Further, if one of your friends comments to your "help me" post on Facebook, then there will be many strangers (NOT on your friends list) who will be notified that you're desperately stranded. Conceivably, one of those strangers may be twisted, may go out searching and may not have the nicest of intentions.

Regardless, if I were desperately stranded, then I would try to contact both 911 and Facebook. There is a chance that communication with 911 may not be the best. Perhaps the phone call gets cut off midway, or your battery dies or whatever.

With the message to Facebook or similar, there just needs to be a quick burst of data to be sent on a half-ass connection. Those who really care will take the necessary steps to ensure your safety. Those who don't care won't do anything. Plus, you can update your Facebook comment later. If you're like me, then you don't have too many friends on Facebook anyway. In my case, I doubt the rescuers would be overloaded with phone calls.

I'm not currently setup to contact Facebook via my cell phone. However, because of this thread, I soon will be.