I really dig the Kindle 3. The small improvements add up to a significant improvement in usability. As my friend Chris put it, "as soon as I turned it on I realized I did the right thing."
The patch is big and noisy, but here's what stands out: Ingo's RT kernel, which converts most spinlocks to priority-inheriting mutexes, removing most regions of non-preemption in the kernel; ARM architecture updates; driver for the Atheros AR6002 802.11a/b/g device; driver for the Freescale MC13783 voltage regulator; driver for E Ink; driver for the Asahi-Kasei AK4647 audio device; lots more.
From the source, the Kindle is still code named Fiona internally.
Anyone spot anything neat I am missing?