I'm so torn. I've been very happy with my Panasonic plasma for the last seven years, and have had absolutely no issues with the tech. After the break-in period and some tentative experimentation, I gleefully abused the heck out of this display. Spotted a little IR a handful of times in the first 18 months (4:3 bars; game HUDs), but it always faded quickly, and I haven't seen a trace of it in years. However, I get the impression that this kind of careless use won't be possible with newer models; plus the idea of using a new, larger display as an occasional PC monitor is very appealing. So plasma seems like a less sensible choice this time.
Looking at LCD tech, I'd go with a Samsung 8000; but while the PQ is superb for an LCD, the input lag is unacceptable. The Sony W9 lacks the lag, but seems to couple an inferior display with a much higher price tag. If I did go plasma, I'd be forced to pick up an S60 for the low input lag, but I'd have to compromise my use to avoid IR; and I'd also lose 3D. I don't want to trade IQ or pay through the nose for it, but active 3D is a feature I'd like in a new TV.
I think I'll wait to upgrade; perhaps hold out for a price drop on the Sony. Seems like the best all-round option, but not for the asking price. If my current panel died tomorrow, I have no idea what I'd do.