It's worth noting that I have about a thousand devices in the field drawing from 1.25A to 2A @12V through the Arduino Vin pin (to a shield), and none of them have burned out any traces or melted any pins in the Arduino =)
Well the issue (and limit) is the maximum continuous forward current rating of the series polarity protection diode wired between the external power connector and the Vin pin. This diode will pass all current supplied to the board and any current consumed off board via the Vin pin. Does anyone one know the actual diode part number used and it's max forward current rating? I have no doubt one can draw more then it's safe rating but it's not an accepted good engineering practice to do so. I always assumed it was a bog standard 1 amp diode?
Lefty