I agree with those who question the heatsink theory. Sounds nifty, but for one thing the TP2 runs cooler than did the TP1, and as others have pointed out, neither Sprint nor Verizon's back covers have any ventilation.
Also, my Verizon cover doesn't have any pieces of metal affixed to it, as was described by a couple users, which allegedly performs some sort of heat-mitigation task. Perhaps I misunderstood where that piece of metal is.
One thing I will also agree with that was posted in this thread is the risk of using some protective phone cases, as they also tend to prevent heat from escaping as efficiently and may lead to over-heating during calls.
