I got Debian running, and currently helping out to get armhf port in shape.
Debian currently has armel userland which aims to keep compatible with most possible devices out there, that makes it not possible to deliver all horse power, but sufficient to run it.
A more optimized port, named armhf, was proposed by Genesi as it is capable to deliver all the efficiency on the Genesi hardware. The port is still under development, but it is usable. You'll find more information about it at http://debian-ports.org/
. I am maintaining packages for linux mainline kernel with some extra patches which support both EfikaMX and EfikaSB, those are still in a very early stage, but you'll be able to boot the device and get the most out of it.
-- Hector Oron <zumbi>