If I understand the article right, this is an RPI without the ethernet, HDMI, etc and just has all the headers that would make it fit arduino shields. Hummm…I think I would stick with arduino’s which are starting to drop in price (lightake just had an uno for $17 shipped).
http://dangerousprototypes.com/2013/05/13/embedded-pi-bridges-r-pi-or-stm32-with-arduino-shields