Update: We got some new details about these new displays.
Samsung has announced their latest AMOLED display, the Super AMOLED Plus. They say that the new display feature 50% more sub-pixels, and also features improvements in contrast and outdoor readability over the 'original' Super AMOLED displays. Samsung also announced the first phone to sport these new displays - the Infuse 4G. The display is a 4.5" one, the largest AMOLED Samsung ever made!
Back in July 2010, Samsung announced that they plan to soon double their AMOLED displays' efficiency, lifetime and power consumption. Perhaps the Super AMOLED Plus is the result of that research. We first heard of an upgrade to the Super-AMOLED technology in November 2010, we thought the name would be Super AMOLED 2.