I just got my iphone yesterday and cannot replicate the problem. I thought maybe I was in a good signal area so today I went to an area where I know signal is poor. When not in my hand the phone sat at 3 bars. If I touched the spot I could get it to bounce around from 2-3-4 bars. Never once did it go to no signal. Also, no matter what hand I hold the phone in my particular grip doesn't naturally touch the spot.
A friend of mine who also just got his phone has has the same experience as I have. No real issue.
Another friend who received his phone on launch day can touch the spot and go from 5 bars to no signal in minutes.
The only commonality between the 2 phones that appear to have no problem is that they were bought at best buy from a very recent shipment. The phone with the problem was bought from Apple and received on launch day.
IMHO, the biggest problem with the whole situation is how Apple has handled it. Clearly some people have issues, but Apple being Apple has been arrogant about the whole ordeal. This is one time where a little communication would go a long ways. I'm going to guess they still aren't sure of the exact problem and that's why they have been totally quiet on the issue (other than SJs typical quips).
Also, the whole design defect thing needs to have some logic enter the equation. Do people really think that the phone went through an entire hardware design cycle and a group of engineers never thought to test of the phone was held? Even the worst developers I've worked with and managed do better testing than that. I think it's much more likely that there is/was either an issue with software and/or manufacturing.
My friend with Verizon gets full 3G in the middle of Nebraska. I barely get Edge. No contest.
I think it'll eventually blow over, and I think we're starting to see signs of this in the Apple press already. I suspect Jobs knows it's a relative non-issue and is trying to brush it off as such. Unfortunately, it is an issue new iPhone users are concerned about and his words sound callous in that light. It likely would make more sense for Jobs to sit on his words and instead quietly ship the upcoming 4.01 release, but hey, it's Jobs.