[bad_alloc]

The RaspberryPi is supposed to be a computer you can use like a regular one. Rex seems to have a dual role: It's designed to control a robot (lots of pins and extension boards) and to act as a general purpose computer. So it sits somewhere between an Arduino and a RasPi.

[georgemcbay]

The BeagleBone Black also sits in that range in that it is both an ARM-based general purpose computer but also has 2 real-time programmable microcontrollers onboard. Which isn't to say that this Rex project has no value, if it is produced it would be a much easier out-of-the-box experience for someone to just plug in some garden variety I2C motors and get going than it would be on the Black, but this sort of combined computer/microcontroller design isn't unique to it.