Still loving the 60" ST60. This is my first plasma, and it replaced a UN55B8500. Couldn't be happier. No buzzing, No fan noise.
I'm not seeing persistent IR (that I can detect). BUT, I do watch a lot of pixar movies (kids). Haven't watched too much cable with persistent logos. I think I see a hint of IR here and there, but its gone by the time i scrutinize the area of the screen. I have to be looking for it to see a hint of it. But it could be my own eyes doing their own IR from staring at sections of the screen. In other words, I've stopped looking for IR and am just watching the TV now
The image looks sharp (contrary to what others say) if the source is sharp. HD cable though is spotty. I have comcast, which likes to bit-steal their way to victory. Pretty much they try to run most channels at 12mbps or less by using a stat-mux like approach to take the provider's signal and bring it down to 12mbps. Some channels are lucky and get more bits, but most don't. We have made some equipment for them, and I am aware of why they do this. Unfortunately, they have convinced themselves that their special approach to reducing the quality of channels is "not noticeable to consumers" but it IS. And, oh yes, this is MPEG-2 we're talking about, so 12mbps and less isn't so good for most HD content (pure animation can get away with it and look decent). Why do I ramble on about this? These low quality re-conditioned channels (to save bandwidth for the MSO) make it appear the TV is dithering like crazy, causing tons of swimming pixels and even lots of banding in content. Good news is this can be seen on any of the hd tvs in my house, but I do know people assume its their TV.
Of course the apps in this TV aren't great but they work. Unfortunately using built-in netflix & amazon instant video do not seem to let you change screen format (ie, to zoom in to get rid of black bars).
Blu-rays look great (of course). Much of the streaming content from Amazon & Netflix looks better than the average HD cable channel for us.
I have this TV paired up with a ZVox 555 that it sits on top of. I like the setup since this is a bedroom TV.
Now that I have a plasma, I'm worried about the state of the market after hearing about Panasonic's rumors (no more plasma; may exit tv business, etc). I hope plasma lives on until something better comes along. I am a convert now after this ST60.