As always, the new iPhone 4 is not just a phone, but a piece of art. But with art, there is also a reception issue. There is a metal band that surrounds the iPhone 4 that doubles as an antenna. If you hold the iPhone and cover the bottom-left corner of the phone and bridge the gap between the notch , it could potentially cause a reception problem.
So when an email was sent to Steve Jobs stating the problem, Jobs had a great response:
You gotta love it! On a serious note, iPhone 4 users are being told to grip the phone without covering the band as explained above. May I suggest using the speaker option that doesn’t require holding the phone at all! LOL
On a 2nd serious note the problem seems to affect those who are left handed. Also using a case cover will eliminate the problem as well.