One small comment concerning Best Buy and the Sony display. When I was at the local Magnolia, the Sony was running Sony content that was outstanding. Every other TV on the wall at Magnolia was running the standard in house feed which comes over cable and if I remember correctly is 480i.
Using this criteria, the Sharp Elites (60" & 70") looked terrible. The Panasonic VT60 looked terrible. The Samsung FT8500 looked terrible. I know there were a log of other TV's on the wall, but none was of enough interest to make note or make or model. Besides, they all looked terrible also.
My last three TV purchases were based on reviews from Cnet other on-line reviews plus comments or reviews from Kevin Miller, D-Nice, Chad-B, etc. After a good calibration, these guys know what the TV's are capable of.
I am in the market again this year and will most likely buy one of Cnet's current top units that also were the top units at Robert Zohn's shootout.
I am also on my third plasma. It resides in a closed cabinet and I have never had any issue with heat or IR. I do have some washouts from the morning sun (room faces East with a large arched window (60"w x 30"h) above a 60" x 60" picture window. Also, unfortunately on darkest content can see the reflection of one lamp in the living room. Lamp is on if watching junk TV and reading at the same time. When switching to a Blu-Ray, lamp is off so not an issue.
Damn. My small comment turned into an epistle.