I have not personally had any issues using the iPhone 4 for calls. I also haven't been able to kill phone calls through the left-corner "Grip of Death".
That said, I also haven't gone nuts trying to replicate it, either. I have tried a few times, and if I hold it just so, I can make the displayed bars drop a little. However, why I'm not having problems of my own:
- I use the Apple bumper on it. Bought it the first day before there were any reports of issues. I like the look of it and it protects the phone pretty well. Could be a little tighter, though.
- I typically only hold the phone in my hand to place calls, check voicemail, and use Internet apps. For calling, I pretty much keep it in my pocket - I almost always use a headset (and in the car that's an absolute). So I'm not likely to see a grip-related issue in my daily use.
- AT&T coverage is pretty good on most of the North Shore and has been for the last couple of years. We still have a few dead spots (Manchester, Beverly Farms, the beach in Marblehead), but overall signal is pretty good here. Te antenna issue mainly kicks in when you are in a marginal signal area. That's why the Apple letter on the iPhone 4 last week (annotated brilliantly by Gruber at DF) wasn't a total weasel. They do have a point.
- There were some spots on my old iPhone 3GS that were pretty much guaranteed call-drop zones. Going by Beverly Airport southbound on Route 97 was always a dropped call. Heading down the bypass road into downtown Salem would drop calls as I neared the train station. Driving through the northern part of Rowley on Route 1. Those spots do not drop with the iPhone 4 so far, period. I don't use the phone any differently in the car now than I did before - same handsfree, same mounting bracket (the iPhone in the bumper fits a little looser than the 3GS did in the Griffin Reveal - and by the way, the Griffin Reveal for the iPhone 4 is pure crap). It just works better.
- If Apple announces some kind of repair program or recall, will I participate? Heck yeah. I have a really good phone, and I'm not really having any issues with it - but if Apple makes a change to improve it I'm all aboard.