One of the most beautiful displays I saw at SID were E Ink's latest color e-paper panels. The Advanced Color ePaper (ACeP) is a high-quality full-color E Ink display that is enabled by colored pigments and not color-filters like in E Ink's older color displays.
The ACeP on display were 20" panels with a resolution of 1600x2500 (150 PPI). I have to say that these displays were simply stunning - real paper like quality. This offers a different image quality than an OLED display (and much slower refresh rate and specifications) - but for some applications I think these displays may be perfect. I can't wait for E Ink to commercialize them - but it'll take a while, E Ink estimated it will take around 2 years.