People we get to thank for actually designing the board: Massimo Banzi, David Cuartielles, Tom Igoe, Gianluca Martino, David Mellis and Nicholas Zambetti.
Let's start with the board pinout: http://www.arduino.cc/en/Guide/Board
Look at Arduino Playground for code + ideas http://www.arduino.cc/playground/
http://www.b1t-m0nkey.com/code/arduino_snippets/