Is my LCD TV doing some sort of dithering?
Does it appears like vertical blending from incorrect row number sync? Like 1920x1200

Make sure the TV is pixel sync'd to the video signal using the onscreen menu (often advanced mode ?) to ensure no overscan on vertical, horizontal and no aliasng.

To verify this , use one of the first test pattern with alternating black white pixels then alternating 2 pixel pairs, then gradient colors to check gamma for each color. http://download.cnet.com/Dead-Pixel-Tester/3000-18512_4-82448.html

DPT.exe can also be used to toggle and small zone to restore dead pixels by discharging with AC video pattern.