Unlike an iPod or a cellphone, an HDTV includes numerous and sometimes very advanced adjustments that can directly improve its performance. Using those controls properly can have more impact on picture quality than any other factor.
I made the following measurements via the DVI input from an upconverting DVD player:
Color temperature (Warm color temperature, Cinema gamma preset, Night mode before calibration): Low window (20 IRE): 6,353/6,464 K High window (80 IRE): 6,879/6,531 K Brightness (100-IRE window before/after calibration): 119/41.3 ftL
When a plasma TV isn't displaying an image, the stuff behind the name is just an inert gas - usually a mixture of neon and xenon - but it's a big part of what allows these TVs to measure just 3 to 6 inches thick.
I've been impressed by the image quality of many of the 1080p HDTVs I've seen lately, but to me the biggest surprise over the last year has been the excellent pictures produced by variants on LCoS (liquid crystal on silicon) technology. LCoS uses light reflected from silicon chips covered with liquid crystals - 1080p models boast more than 2 million pixels' worth.
Did you know you can get a plasma HDTV for $1,800? That's right - TV technology that a few years ago cost more than a Hyundai is now within reach of most middle-class American budgets. Prices for entry-level big-screen HDTVs, including those flat-panel plasmas and LCDs as well as advanced DLP and LCD projectors, are falling at near-terminal velocity and have yet to hit bottom.