Plasmas will eventually die out as they are more expensive and less power efficient than LCD's.
Panasonic's mass production line for plasma is really pushing the price down considerably, and its certainly a better image quality than most LCD panels.
In terms of power efficiency, its an urban myth that plasma's are horrible power hogs. LCD panels use the most power displaying a black image, and plasma uses the most power displaying a bright white image. But overall both tech's are better than CRT if you work out power per "inch" of the display.
A good Plasma's only 10-15% more power hungry than a good LCD panel of the same size. Of course if your compare a 40inch lcd and a 42inch plasma, the extra size of the plasma will certainly affect the power requirements. (The paper specs for plasma's virtually always qoute maximum power, rather than "average" power). My own set claims just under 300W, but in reality its more like 180W, and on dark Sci-Fi it can be as low as 90W
Thats the thing, Plasma's power changes dramatically based on the image displayed, but LCD is more consistant, as the majority of the power is running the backlight.
Sony pulled out of Plasma, because they never made any Plasma panels inhouse. They were just branding someone elses plasma panels. Now they have a 50/50 ownership of an LCD factory with Sharp. Thus sony pulled out of the plasma market.
Pioneer had a good stab, they bought NEC's plasma fabs, and brought out the stunning Kuro panels. But Panasonic and Samsung have been targetting the mass market, and producing great (but not stunning) panels at a faction of the price. Apparently pioneer will have the kuro panels made by another oem, using current Kuro tech, so they will continue to sell plasma sets for some time. ( It may be panasonic making their panels once the deal's all sorted ).
Panasonic are still putting millions of dollars into research of plasma tech, as demonstrated by their 37inch TrueHD panel, and their crazy 150inch 4k panel. Samsung also still seem to be in the game for making consumer priced Plasma panels.
Oled is still a long way away, I believe there are issues with the lifespan of the blue oleds, at least compared to the 60k halflife we see on modern plasmas. (And dont forget the backlight can fail on an LCD set, and its pretty much a bin job if that happens). Plasma sets just gracefully fade away over the course of around 10-20 years... Although there are plenty of other things that can go wrong long before that, and as we seem to live in a throwaway society these days even a minor PSU fault can be the end of a TV.
