Do OLED screens flicker? I think they do because in a video I saw of the optimus maximus the keys were filckering.
No. And they have response times in MICROseconds, so there is no ghosting or lag either. The flickering is likely due to the video, possibly the frame rate of the video interacting with the framerate of the lighting. OLEDs are rock solid, better than either CRTs or ordinary backlit LCDs.
I'll add that I'm all for Apple adopting OLEDs - no need for a backlighting unit therefore thin, ultra-fast, perfect when wiewed from an angle (unless Apple puts a glary sheet of glass in front), potential for great colour gamut and a life-time that is sufficient for portable computers.
I can't help recalling when we bought the Apple 180c - the first laptop with an _active-matrix_ colour display. No submarining! Colour clarity out of this world! Outrageous price! History might repeat itself.