With the latest release of SignalLoc, I've added the capability to lookup latitude and longitude of GSM cell sites using a Google API. Basically it's the same mechanism Google Maps uses.
http://www.blackberryforums.com/afte...erry-beta.html
If you've got a GSM handset, try SignalLoc and see if you get the lat/lon of your cell sites. Then, turn your GPS off and try Google Maps. With the GPS off, Google maps will display the cell site location with a large radius as your location. Compare the two and let me know if they differ.
Thanks.