Looks interesting, although the potential problem with anything running Linux is to get good enough real-time performance. It's generally preferable to offload the hard real-time stuff to a separate processor. What would be really interesting is to take the 4-core Raspberry Pi, hand 3 cores over to Linux, and dedicate one to the real time stuff.
You can already get 3D printer controller boards that run web servers, e.g. Duet and Smoothie. I think the real benefit of attaching something as powerful as the RPi to a 3D printer is if you want to add streaming video, or do slicing on it as well.
Have you seen that the RADDS is being sold bundeled with the UDOO-Neo?
I wonder how the software solution looks like for it. Can´t be that complicated, but how does the Linux platform connect to the integrated arduino due? Virtual USB?