I have been doing a lot of research on tv's since I am going to work in electronics. basically lcd is something that will last for a long time, the picture will be good, an color will be good. Plasma you can't really fix if it breaks, it will be very fast, and have a lot of detail and you get true colors with. Also you don't see blurry reflections on a plasma screen as you would a lcd. I wouldn't buy led yet because its to new and they have a lot of kinks to fix an they are pricey.
if you think of it as a picture book, the lcd has 50 pages, the plasma has 5000. you only get 50 pages to make someone run across a football field, but with the plasma you get 5000, so its more detailed.

as far as brands, i would stick with samsung, sony, Panasonic.