AMOLED screens provide richer colors and deeper contrast than a normal screen is capable of. Unfortunately, they are also power-hungry and handle direct sunlight about as well as a coven of vampires. Samsung's new Super AMOLED display purportedly deals with many of the issues felt by normal AMOLED displays. Techblog (via Android and Me) did a side-by-side study to see just how well the new tech works.
From the video, we can see that Super AMOLED is substantially better in light than older AMOLED screens. The traditional LCD screen still has the direct-light advantage, but it is clear that OLED technology is well on its way to being more practical for use. We're not that far off from a world where traditional LCD displays fall under the advance of OLED and retinal displays.