According to the NYT, a "person with direct knowledge" of the iPhone 4's design indicated that the device's reception troubles would be fixed by a second software update—one different from the iOS 4.0.1 update made available earlier today:
One person with direct knowledge of the phone's design said Thursday that the iPhone 4 exposed a longstanding weakness in the basic communications software inside Apple's phones and that the reception problems were not caused by an isolated hardware flaw.
Instead, the problems emerged in the complex interaction between specialized communications software and the antenna, said the person, who agreed to speak on the condition of anonymity because he was not authorized to discuss the matter.
The person said the problems were longstanding but had been exposed by the design of the iPhone 4. All cellphones can be affected by the way a hand grips the phone, but well-designed communications software compensates for a variety of external factors and prevents calls from dropping, the person said.
It seems hard to believe that a problem caused by skin touching the metal of an antenna can be fixed by software, but hearing that explanation doesn't seem as impossible as it did before: Software and hardware together could be causing the problem—and software could fix it.