We had no less than 4 new iphones activated today, all of our family. We were all very concerned about this rumor as we already have pretty iffy 3G reception in our neighborhood to start with, so as soon as we got our shiny new phones we all immediately checked that issue, trying to hold the phone in every imaginable way, with either hands. NONE, of our iphone4 showed any lessening of the 3-4 bars we all displayed no matter how hard we tried to cover and touch as much of the metal frame/antenna on the iphone. Not only could we not repeat the issue, but all went to sit in our respective cars, in our carport, where we typically could not initiate a call reliably, and all of us suprisingly managed to place a call successfully with a full 1-2 bars!!
Moreover, a few hours later, when my neighbor David stopped by to share his excitement for his own new iphone4, he wasn't aware of this so called issue, and we also tried to weaken his signal strength by holding the frame the way it supposedly trigger the drop, but no go, he also had a steady 4 bars on his iphone! Now, I know that a mere 5 iphone sample is not much to stand on, but the fact that none out of 5 manifested the drop tells me that it is definitely NOT a widespread issue, if an issue at all...
AAPLy yours.