Super AMOLED 2 was rumored to be the brand name of Samsung's 2nd generation Super AMOLED displays. In 2011, reports suggested that Samsung will use Super AMOLED 2 in its upcoming flagship Android phone. In the leaked slide you can see below, it lists a sAMOLED2 display technology:
This Super AMOLED 2 display tech was never released, and Samsung simply kept branding its high-end AMOLED displays as Super AMOLED displays - even though the company kept improving the display technology and increase its performance.
Super-AMOLED displays feature an integrated touch function over a regular AMOLED. Samsung has placed a touch-sensor (on-cell) over the display and made it evaporate. The thickness of the touch sensor is just 0.001 mm and this allows the screen to provide better images and to have great visibility even in direct sunlight (Samsung says that they perform 20% better than regular touch AMOLED outdoors). Super AMOLEDs also have better lifetime than regular AMOLED and are very responsive to touch. Super AMOLED have been announced in January 2010.
Super AMOLED explained and some cool videos
Here's a nice video interview with a Samsung employee that explains how Super AMOLEDs work and why they are the best displays around:
Here's a video comparing the Super-AMOLED to the iPhone's LCD. Check out the great contrast ratio and viewing angles:
And finally here you can see how the Super AMOLED behaves in direct sun: