We live in an area with medium to poor signal strength. Using the iPhone 3G we average 2 bars. Call quality isn't great and some calls get dropped. It is not a wonderful experience, but workable. I upgraded 2 of our family's phones yesterday and the iPhone 4 phones are getting either 1 bar or "No Signal". Call quality is terrible and many calls are dropped. At the same time, the remaining non-upgraded 3G is performing as always. This is not a "death grip" problem because we've tried holding them various ways. The iPhone 4 phones also show low or no signal when just sitting on a table untouched. Holding them with the "death grip" almost guarantees "no signal". I've read some opinions that the iPhone 4 simply displays the signal strength differently, but the reduced call quality and more frequent dropped calls indicates that this is more than a simple display issue. Overall, we are rather unhappy with the iPhone 4.