Dynamic Contrast Ratio, Static Contrast Ratio, Refresh as well as the obvious resolution are what count a little more than Plasma or LCD to me. I was high on getting an LED TV until I realized LED TV's are a misnomer as the LED TV is an LCD TV with an LED back light.
Static Contrast Ratio is the contrast ratio at a given point in time.
Dynamic Contrast Ratio is the overall contrast ratio the television can produce over time.
When I bought my current TV, I was going with Plasma because it has a better picture, but then they don't last as long and are more likely to have glare. And the real kicker, Plasma were more expensive than LCD by 10-20% at the time, lol. I went with LCD.
I'm looking for something that has the following.
40inch or more
LED LCD or LCD
120Hz or more
1080p resolution
DCR > 100,000:1
If my laptop and TV both sell, I'll have about 700 to drop on a TV that fits those wants. Needle in the haystack is what this feels like and there's so damn many TV's ... crazy go nuts.