Consider the following detaiils before buying your HDTV 

 LCD vs. PLASMA LCD TVs have a backlight that's electronically filtered to produce the microscopic color pixels that make up the image, whereas plasma TVs have pixels that emit colored light themselves. LCD TVs are better than plasmas in bright rooms and are very affordable up to about 42 in. Plasma TVs offer deep blacks and rich colors and can be viewed from wider angles than LCD TVs and are available in larger sizes.

• CONTRAST RATIO This ratio (e.g., 600 to 1) represents the difference between a screen's brightest and darkest colors. A higher ratio is better. "Contrast as a concept is really important," says Poor. "The blacker your blacks, the more punch you have to your colors." But TV makers use differing standards to calculate the numbers, so comparing them is "almost useless," says Poor. So how do you judge contrast? First view the TV from the front, then see how badly the image fades from the side. If all the sets are on the same channel, it's fairly easy to tell which ones have deeper blacks and purer whites.