iPhone 4 overheat warning and PS

Hi there,

I was originally waiting for the white one but seems like it's not going to be released by the end of this mo. So, I'm looking into the black one. But I do have a couple questions.

1. Is the Proximity Sensor problem affect majority of the ip4? Or just the minority?

2. How about the overheat warning?

I am wondering if the later batch has fix some of these problems already. And I would like to have some feedback from the users.

Thanks!