I had these "newton rings" on my UC Cell TP1 (zagg invisible shield case) and TP2 (default screen protector). From reading
this thread supposedly it's caused when there's pressure on the screens causing a problem with the touch screen layers. Running android doesn't cause it, having a screen protector doesn't cause it. I usually hold my phone with my shoulder to the side of my face, and once I get my desire (hopefully it won't happen) I've started practicing holding my phone with the not touching my face. This should help eliminate this problem from future phones, although I believe it's a problem with HTC screen manufacturing process, as no other phones I've had show this issue.