I'm with you NatCh. My whole reason for popping into the thread was to see if there was more info on that front light.
The image on engadget is really hard to figure out. An iddy biddy e-ink display in a gymondo case?
Given the coloration of that picture, the front light most likely uses a very tiny LED, or an array. This is good for battery life, though in relative terms, it will be a lot worse than the Reader's current 3 week average.
Great news! Now, the biggest issues are going to be (a) getting these into the Reader, and (b) making sure the LED isn't too blue.