@ seaedge - Well explained re. the tech behind GPS.

The purpose of the GPS within the iPHone 3G is really not so much for in-car navigational purpose, but more as a backdoor for future location-based advertising for commerce. The google map in matured markets have various POI which includes commercial retailers. So when you activate the google map in iPhone, the map immediately shows u where u are and if u type say, pizza, or at&t, it will show u the locations of these outlets within your nearby vicinity.