Oh I have a theory! All the reviews about the Story HD complained about the contrast. Now there are two new ereaders with the 1024x768 screen and they both have built-in lighting. Could it be that it IS the same screen, and the lighting is necessary to make up for the poor contrast?
I can't wait for the Kobo Glo and the Paperwhite to be released, so we can see a real comparison of all the screens, with light on and OFF.