I have started some further documentation of the Arduino Mini: http://www.arduino.cc/playground/Learning/ArduinoMini
I'd be happy if someone could correct, in particular, the instructions on how to program the mini via an NG board. I haven't been able to test these yet (my mini looks dead, but that's for another post).
Eventually, we can pass this documentation back to the arduino team to add to their official Mini page: http://www.arduino.cc/en/Main/ArduinoBoardMini
Perhaps someone could contribute a little note for newbies on how to use a diode to avoid powering the wrong way, as this reportedly kills the mini, which is too small to make a good paperweight.