Hi. This is my first post here. I took the case off of my 32GB iPhone 3GS today and noticed a hairline crack about a quarter of an inch long, coming up from the USB area on the back. I was about to book a Genius appt., but then I wondered; if I wait till after the iPhone 4 launch, will they replace my 3GS with an iPhone 4? I know this is probably a pipe dream, but I figured I'd ask. Thanks in advance.