Wow guys, I think I have got the reason why because of a conversation I had on the Google Panoramio help/support forum! Exactly, it is not the latitude, but the longitude!It is because our earth has a daily turnaround. GPS satellites are in geostationary orbit. They tell the point on the fictional sphere, but the place on earth depends on the time of day. This means that if something is wrong with the clock setting of the camera, like summer/winter time setting, then there will be a longitude deviation! It is that we have Lawrence here for many good answers, but the Photosynth team is doing a very poor job on supporting its community!