The last batch of Samsungs had horrendous bowing problems. The new thin bezel could not support the screen and it would bow. I'm not sure about the new tv's. I've called and emailed Samsung at least a dozen times asking specifically if they've addressed this very well known and documented failure. They have yet to tell me anything that would ease my mind. That being said, next time you see the tv, put the guide up where there's a long straight line and see if it curves up near the sides like a smiley face. It usually shows about 5 to 6 inches from the sides near the top and bottom of the screens. Touch the screen and you see the entire picture move on most Samsungs.
As far as LED goes, unless they've made dramatic inroads, I still say go with the lamp. I have yet to read any favorable review of any of the existing LED Samsungs and from what I read on another forum from folks who were at the big Ceida show where they had them on display, they weren't impressed either.
You have to judge for yourself, however, since there are tons of very very happy Samsung owners. Often times you only hear the bad. Let your eyes tell you what you need to know.