So I'm late to the game, but my regular jetBook has had flicker ("quiver") problems from the beginning. As most, it happens in sunlight or partial sunlight as makes the letters look like they are shaking. Sometimes it is more noticeable than others. I don't read outside enough for it to bother me, but when I do, I tend to ignore it. IMO it's a screen issue and not a defective unit (unless lots of people have bad units...)
Since I dyed my JB blue I can't send it back anyway, so I have to live with it.