Believe me ive been "paranoid". i wouldnt have been as freaked out if didnt know about those things. I always have my gps "deactivated" dont even use it for directions ever.. you can never truly deactivate any cellular device that uses gps even pulling the battery, They have the same tech as some nice alarm clocks have, that little back-up battery that has just enough juice to keep all your information "safe" and "beaming back to scotty".
It probably has more to do with ip address than gps location.
Anybody of you open a google search and search for "what's my ip address", or simply go to this link
http://www.ip-adress.com/There are hundreds of pages that will show you what's the ip address assigned to your computer, and from that, the networks knows where are you located -actually it knows the location of the Internet Gateway.
If you have been travelling and using the Blackberry to connect to the internet, you have been assigned different ip addresses. If you have some kind of automatic connection with facebook, it can now from there where have you been.
Why not killing your facebook profile altogether? I did it long time ago, it was extenuating pretending to be cooler than I actually am.... :-) no regrets whatsoever. No twitter, no linkedin, only memberships in cool internet forums :-)