Read reviews..Going into a store to compare is useless in most cases. The sets in the stores are not configured correctly, the lighting in the room is glaring and in most cases you can't bring your own material to do a comparison.
The more reviews you read - the better buying decision you'll make. As easy as that.
I used to think Full-HD (1080p) was important when its really not.
My tip right off the bat is a Panasonic plasma. Burn-ins is almost impossible and they come in 1080p nowadays if you really wanna pay the premium.







