We've barely heard anything about Pixel Qi lately, but that has changed and, hopefully, we'll see the displays more often down the line.
Pixel Qi panels are different from common displays through their ability to operate in transflective mode.
Essentially, they can absorb ambient light and, thus, don't need a backlight during the day, leading to low power needs.
Even more importantly, they are totally clear even under the brightest sunlight, as opposed to most other screens that aren't that good in similar conditions.
Alas, despite their benefits, Pixel Qi panels just haven't seen much success. Still, according to this recent blog, the time may come when all will change.
So far, about a dozen consumer electronics devices utilize Pixel Qi screens. Higher-resolution versions are on the way, all of them featuring a lower power draw, but no ETA was provided.