The Touchscreen – Glas of the iPhone 3GS is slightly inclined. Just put your Finger in the middle and squeeze once to the left and once to the right: You will notice that on the right end you will notice a little edge that results from the Glas not being inserted completely flat. Maybe thats just on German iPhones but I noticed that “artificial edge” on 3 iPhones today. Could be that Apple decided to do it this way to help find the correct orientation while fiddling around with the telephone in the car or other situations where this “tactile” Feature helps.
you’re right. mine is the same (italian phone). always thought this is due to manufacturing irregularity.
@Tobias: Oh, thats interesting..it really seems to be like that on all Devices!