I am sure everyone remembers the scandal before when the google street view cars where collecting wifi access point information, a genuine mistake they called it !!. Well you can stop google collecting information about your base stations, or prevent them using them as a way to pinpoint locations using nearby wifi base stations.
All you need to do is change the name of your SSID to add _nomap, so if your SSID was Dagobah it will now be named Dagobah_nomap. This is a major pain if I'm honest why shoudl users have to make changes, this kind of issue should really be "opt-in". If you are concerned about google collecting information and using your base station then you may want to consider it.
Google has detailed this on their blog, you can read that post here http://googleblog.blogspot.com/2011/11/greater-choice-for-wireless-access.html
I am always interested in your thoughts so if you have any comments or feedback then please feel free to add any comments, or you can mail me here.