retrolefty:
It's not as simple and straight forward as you might think or wish. And of course the users would have to first have the proper arduino USB driver installed to recognize their board when plugged in. And not every user will have the same com port number assigned to their arduino board. And if users have different arduino board types (say Uno Vs Mega) you will have to be sure you send each user the proper unique .hex file.
They will all have the same arduino model. And setting a com port is farily simple to walk someone through. I was reading a small amount on using the AVRDUDE and your right about not having a perfected guideline. Now the issue you brought up about the OS is a new thought for me. And your quite right... I wonder if there is a way to auto load a sketch from USB.
If I add a USB port to the arduino could I set the current sketch to overwrite itself with the sketch on the USB stick? Thats just a shot in the dark but you guys are getting the gears running in my head. Any other ideas?