That is quite some board! Arduino has certainly progressed, I'm still playing around with R3 boards and ATMega chips. Other than the form factor, this looks like not only a completely different class of product, but a completely different hobby or business.
ATmega micros are still incredibly useful and the Arduino ecosystem (especially the open source libraries, thanks Rob Tillaart!) makes it so easy to whip up a firmware. I really hope no matter what happens Arduino doesn't go off the rails.
