I think the whole industry peaked a couple of years ago.
Part of the reason is that of the US digital broadcast changeover dropping of analog broadcast. Another part of the reason is the worldwide recession, stagnation, brought about by the banking crisis. A third part of the reason is that prices have been falling so of course quality declines. My 42" Vizio from 2007 weighs 80 lbs and built solidly with lots of heavy sheet metal in the design/fabrication. Another reason is that the low hanging fruit technological advances have already been achieved in that time period.
Many manufacturers have dropped out or nearly so competition is reduced. Sony scaled back. Philips basically abandoned the North American market in regards to high end sets which it still sells in Europe. Toshiba is in a similar boat these days. Mitsubishi dropped out of the LCD TV market entirely excepting for Front Projection, JVC nearly so, as well (but apparently is making somewhat of a comeback). Sharp abandoned the middle of the market to concentrate on the very small and very large niches. Only LG was a latecomer to the party and late peaker, (though they have been a panel making player from the beginning). Panasonic has entered the LCD market because Plasma which they dominate is floundering, but they reported a $16 biilion dollar loss this year, although Plasmas have been getting better, unlike LCDs. Sharp reported a several billion dollar loss as well.
Vizio VP322 Plasma / Vizio GV42LF LCD / Denon 2200 Silicon Image DVD / Panasonic S97 Faroudja Genesis DVD / Oppo 970HD Mediatek DVD / Oppo 983H Anchor Bay DVD / Panasonic LX-600 Laserdisc / Aiwa MX100 Multi-region VCR / JVC S7600 S-VHS / PS2 / Sega Genesis / Nintendo SNES / Roku 2 XS & HD-XR / Realistic STA-90 Reciever / Realistic Minimus 7 / Antennacraft G1483 Hoverman / Belden 7915A RG6 / Channel Master 7777 Titan 2 UHF/VHF / Panasonic AX-200u / Optoma Graywolf 92" / Draper Luma 92"