The Nook will be supported, too, but the installation procedure requires rooting and hacking the kernel (like TopHat). I believe the Kobo is the better one, but I leave people a choice.

Kobo size will be more practical, specially if you mount it somewhere in the instrument panel area. Rob has made excellent instructions on how to root NOOK, and lately I have been flying with TopHat connected with IOIOv1 and IOIO-OTG cards without connection breaks. I will fly with NOOK until KOBO with IOIO connection is ready. Thanks for the developers!

Compared to DELL Streak operating system update, IMHO NOOK rooting is easy.