Guys, if after getting a replacement from Apple and still having issues...get another replacement!
I was the biggest critic of the new iPhone and it's proximity sensor problems as I had a replacement and updated to 4.1 even though it cost me my jailbreak. I went back to Apple and got my 3rd replacement and it was crap like the others at first (came with 4.0.2). I updated to 4.1 and it actually fixed it! I couldnt believe it. It's been 5 days and not once have I had an issue where previously I had Call Guard register 80 unwanted touched in one 17 minute call.
I now physically see the prox sensor light up red which didn't happen with the phone I had replaced and also can physically see that the screen takes about a second to light up when you pull it away from your face whereas the old one instantly lit up.
Yea, I don't see it lighting up at all. My last one lit up a little bit, but I had to struggle to see it. This one I don't see at all.
I wonder if they're more lenient for 2nd replacements for the same issue because I have 3 problems with the 3 ways for replacements:
1) Send in and receive replacement 1 week or later (obviously not the best case scenario)
2) Advanced exchange. Apple sends out a replacement immediately, but puts a hold of the price of the phone on my credit card. My credit limit (as a college student) is $500, so this obviously won't work.
3) Take back into an Apple store. Closest Apple store is 106 miles away. I'm not making another drive there for the same problem. The only reason I chose this approach is because it's on my way home. I'm not planning a trip home for another few weeks.