I've had a Panasonic 46PZ85U plasma for about 6 months now. There is a lot of IR when it gets heated up and you look for it, but I've had ZERO permanent burn-in. It kinda bugs me b/c I'm always afraid it might not fade away, but it always does perfectly. You have to stick your face about 3 feet from the TV and make the entire screen black before you can see any of the IR anyway. Normal viewing, and you never see it. I'm SO glad I went plasma. Blacks, colors, clarity, natural looking picture and motion (none of that 120hz crap), etc. are all stunning. 6 months later and I still pinch myself when watching a bluray or playing PS3 on it.
If you've got a bright room, the only downfall is it will glare in sunlight. From my experience, Panasonic plasmas are great for PS3 and they can be had for a pretty cheap price compared to "similar" LCDs. For the price, I don't think you can get a better TV. I was actually talking to my buddy this afternoon and he's getting one tomorrow for $600! 42" 720p...the basic model but still a really nice TV.
Sorry if I offended you LCD owners. Your TVs are nice too, I just have a mancrush on plasmas.