Someone is working on a Braille eReader that generates raised dots dynamically, as the user pages through the book— sort of three-dimensional e-ink. I'm not sure if this is as useful as the text-to-speech function of the Kindle, but it is nice for the blind-from-birth folks for whom reading Braille is the natural way to read books. That's especially true if it can work with any ebook.
Someone took the trouble to figure out how much it costs to build a Kindle. Leaving out what Amazon has to pay Sprint for the wireless connection, it came to approximately $186 for the hardware and software, or a little over 50% of list price. That's without any marketing costs. GalleyCat was surprised that it wasn't a lower percentage and considers that means that Amazon can't realistically lower the price any time soon. Although it seems to me if they make and sell enough of them, it's bound to come down.
And finally, Google Alerts clued me in to a new Kindle-users blog that has some useful info on the Kindle, including this excellent comparison on whether it's better to get a used Kindle 1 or a new Kindle 2. The one thing I don't agree on is the battery changing bit. Of course it's better to change the battery in five minutes than to send your Kindle somewhere for days to change the battery!