LCD screens have a more limited viewing angle than plasma. Plasma take a lot more power to run than LCD. The best picture in terms of brilliance and contrast is still from a tube.
In the early days of mass TV, doctors and opticians advised having the wall behind the TV lit with a soft lamp to help prevent eye strain caused by looking at, in effect, a single point light source - the screen. So 'ambi-light' certainly ain't a new idea! TVs screens also had rounded corners then. This was intended to help eye movement and further reduce strain, as it was felt that square corners caused the eye to lock to the image. We live, but don't, it seems, learn.