Just a moment ago I was “locked” out of my Facebook!!! I thought it was a usual Facebook fault, but a few seconds later I received an email from Facebook (attached image).
I followed the process as outlined by Facebook and it eventually took me to a map which had a geo location tag identifying a region of New York. Facebook then asked me to verify if it was me from that location (obviously I indicated no) and so then I went through a process of changing password etc.
Anyway I would just like to say Well Done Facebook – somew of your privacy policies & settings are poor but in this situation your security measure were excellent.