Ace! Someone’s fulfilled my wish for a user-generated mobile coverage map!
The newly launched SignalMap (thanks Gizmodo!) allows users in the US to see how Verizon, AT&T, Sprint and T-Mobile subscribers rate their coverage quality, on a Google Map. Of course, you can also add your own reception markers to the maps.
Unfortunately, the service only covers the US and a handful of carriers - but as the creators say ‘beta is an understatement’ ;)
Imran, take a look at Navizon (www.navizon.com). They are also building coverage maps based on end-user experience but in an automated way. They have a mobile download client that reports back the info. Also interesting is their end goal - they use the signal info for positioning data, i.e. improve upon GPS.