I just got the USB Ethernet Adapter today from my local Apple store... I got it pretty much solely for a faster transfer speed using Migration Assistant, versus the nearly five hours it would take for me to transfer 38+ Gb of stuff from my iMac to the Air via AirPort. Brought it home, plugged it in to both computers, and it said the transfer time would now be over FOURTEEN HOURS long! What the - ?! That was plugged into the right (display port and card reader side) USB port, and didn't try the left (power adapter side).
Plus, I didn't know if it would or not, but also tried to see if I could connect to the internet through the adapter, and couldn't either, as the USB port has it's own IP address or something.
So, I find the adapter pretty useless and without a point to having it, and will be returning it.
I'll be glad to finally have my Air up and running and all ready to go.
Message was edited by: MrJPH: Forgot to specify that the nearly five hour transfer time, was from doing so via an AirPort transfer