Got my Fire keyboard today, and it is indeed very nice.
I think it would look better, though, without the light showing between the keys. (Wasn't that part of the idea of one LED per key?) A thin rubber sheet between the PCB and the keycaps would probably do the trick, but would of course need holes cut in it for the LEDs to shine and for the keycaps to attach to the switches.
I can see that cutting the sheet myself would be enormously error-prone. Perhaps some DeCKite might offer us a template? Or maybe a classy molded sheet available through the webstore, with ridges to go into the backs of the keys and assure no light leakage.
Or maybe I should just ask, hey DeCKers, what'd you do to the keyboard to get the no-leakage pictures on the front page?
Like this one: