Man, I wish people would search the forums, this topic has been done at LEAST 10 times before.....
be careful about the cheap off brands: many at that price are only 720I resolution which means you will NEVER be able to see or view HD content because the tv can't produce it.
The big thing these days is contrast ratios. Better screens produce blacker blacks.
Another thing to look for with LCDs is ghosting (where an image appears behind a fast moving object) like the contrails of a jet.
Burn in isn't an issue with LCDs but it is with Plasma and my Pannie Plasma runs fricken HOT.....
Another thing to watch for is/are number and type of inputs. Many cheaper models only have one or two inputs and if you want to connect more than two items (ie: dvd player and playstation) you'll have to buy an external HDMI switch box (and they can be pricey).
As for durability/warranty. I think toshiba is the only flat screen OEM that has a 2 yr warranty, the rest (even Pioneer when they made the Kiro line) was only a year.
When you do buy one, make sure you anchor it properly. There have been reports of a lot of screens falling over and hurting small kids because these puppies are very heavy and with the slim bases, are tippy.