You are not addressing Apple here - we are just users like you. We don't have any inside track to Apple. We have Apple products like you do, we use them, we read manuals, we experiment with solutions, we try to help fellow users out on this support site.
This is not an Apple Community Forum - it is a user Community Forum. Apple does not see these threads in any formal capacity.
If you want to send feedback to Apple do so here:
http://www.apple.com/feedback/
Sorry you are having troubles. However, the problem seems to be, from these threads, rather random. If some iPhone 4's work and others do not, then there may be a common denominator between those that are not working that we have not uncovered yet.
Any non-App Store apps running? How about where you are located? Any other clues that you can see that might help to track this down? I, personally, am not having this problem with my iPhone 4, so can't help with the troubleshooting from the phone end. However, since this problem is random, the only way we are going to figure it out is to identify the common denominator....any only you can help us do that by providing any information that you think might help.
Cheers,
GB