iOS 4.0.1 Software Update http://snapvoip.blogspot.com/
Apple has released the iOS 4.0.1 Software Update for iPhones. According to Apple : also mentioned in today's Apple iPhone 4 antennae press conference : the update improves the formula to determine how many bars of signal strength to display on iPhone 4, iPhone 3GS, and iPhone 3G. The real signal strength remains the same, but the bars on iPhone will indicate it more precisely.
I have no idea how it displayed earlier, perhaps now it will display more bars no matter what the signal is! Wow, Thanks Apple for the update.