I could care less about the signal problem. The proximity sensor thing is insanely annoying. I am much much more likely to end the call or put it on mute than I am to drop the call due to reception issues. I've exchanged the phone once already and the replacement phone has the same issue. At first, I thought it was my face (shape? texture?), or the way I was holding it (am I suppose to push it with force against my ear to make sure zero space is between the phone and me?). No luck. Right now, all my calls have issues with it unless I put it on speaker phone. But then, I shift the problem from my end to the receiver's end (other side: "what? I can't hear you, can you repeat that, wayne?"). I'd rather them fix how the proximity works, than fool around with how the antenna displays.

EDIT: It seems Apple introduced the bar bug in OS update 2.1 that "improves the accuracy of the 3G signal". Graphical representation of that is here (Source: Gruber): http://fscked.co.uk/post/754590440/this-infographic-hopefull...

So, RDF was hard coded into the bar display (50% = 5 bars?), and the sudden drop shows up if you're at the floor of that green bar, then you use your hand to cover the phone and force it to drop slightly, it will go into freefall mode since you're now crossing the threshold. Fix is to remove the RDF.