Hey, dhbailey, yes the extreme corners of the display are slightly less lit than the rest, but the picture exaggerates it somewhat. I find the entire screen legible without moving the head at all -- once I get it where I want it, of course. The arrangement you can see in the second pic is the one that seems to work best to me.
I think part of the reason for that is because the CCFL bulb is a good deal brighter than any other reading light bulb I've encountered, and part of it is because it's a good deal
larger than those other bulbs.
It also doesn't hurt that the Reader's display is smaller than most paper book pages.