I am in Taiwan and reception out here is quite good so I know it is now a reception issue but I have found that after updating to IOS 5 on my Iphone 4 that I have been getting more and more dropped calls to where I would be calling and would just drop a call. It would also be hard to call back after. Could this be because of programming of the new antenna to where it switches between the antennas on the phone which now exist on the Iphone 4S but not on the Iphone 4 I'm thinking that when it switches it cuts off if there is nothing to switch to. I never had dropped call problems before. 3G reception in Taipei is generally quite good with cell towers every where in the city.