I couldn't get it to boot. The doc says it boots from mmcblk0p3 (why p3?) so I used fdisk to partition the internal card and formatted the 3rd partition with ext3 and extracted the filesystem there (as root).
Still, all I get is the penguin logo (N800) or no reaction at all (N810). The N810 is still on Chinook, the N800 on latest Diablo; is the Diablo bootloader needed for booting this kernel, because my N810 shows no reaction after flashing the kernel?