I've been wanting to mention this for awhile now.
It seems that there is going to be some changes taking place in our displays, whether computer monitors or TV's. Currently, all displays are 3 colors, red, blue, green. In the very near future, they will be red, blue, green and black/white (same pixel).
When you turn down (all the way) red, blue and green, you get dark red, dark blue and dark green, not black. If the colors are turned up all the way, you get bright colors, but not white. Introducing a 4th pixel that can be true black when turned all the way on or, white (transparent- no color) when turned off, adds additional contrast while reducing power requirements for brightness. This new technology does not require different recording formats or broadcasting, it's strictly internal to the display. How the signal is used for 4 colors instead of 3.
The new displays will start out as computer monitors (predominately LCD based), but eventually will be manufactured for entertainment (TV's- CRT and Plasma). If I recall properly, Samsung is going to be the first to produce these devices.
This technological change over isn't decades away, it's going to start in less than a year. I predict, we'll be seeing the new TV's for entertainment in 3 years or less