Actually, the bulk SDRAM/ARM work was done by me in the space of around month (though I only ARM to finally work three days ago with Herman's help).

You could run Linux on ARM using this but you would need to write some more drivers, otherwise you'd be limited to pretty much GPIO/serial/SDHOST PIO.

SDHOST is actually a fairly trivial interface to implement, I'm going to use it in my chainloader but I haven't had the time to look at it yet.