I'm guessing they do this to provide location on phones without GPS, or to improve it. Apple uses this as well on the iPhone (I think) and the iPod Touch. I think they use this company: http://www.skyhookwireless.com/
That's interesting, but it perplexes me as well. I have an iPad/Wifi, and I believe that means it has no GPS. However, Google Maps is able to pinpoint my location almost perfectly, despite the closest mapped street view being more than a mile away on any side.
I suppose it's possible that the mapped my street but didn't publish it for some reason, but that'd be odd.
I submitted this because it's one of those details that may be misinterpreted if one doesn't know what's up ... (while herds of elephants march through other holes, such as the photocopiers' HDs of a couple of days ago ...)
