Talk about Adafruit Raspberry Pi® accessories! Please do not ask for Linux support, this is for Adafruit products only! For Raspberry Pi help please visit: http://www.raspberrypi.org/phpBB3/
The question is pretty basic - is adapting this Arduino robotics kit for a R-Pi a rational project? Its one I'd like to attempt - yet if the people who "know" are ROFLOL then perhaps I'll need to rethink. :-?
You get a good solid mechanical platform to start with. You would need to do a bit of customization to mount the Pi and a prototyping plate. You would probably also need to stabilize the free corner of the plate somehow. Doesn't sound too difficult. Don't forget to post photos when you are done :D