Upload & Sell: On
I was all excited about this on my 1DX as well.
But it's not what I was hoping for.
I, like you, was hoping to just be able to plug it in and browse my camera for photos. Nope.
I was forced to run EOS Utility, and it requires going through a LOT of settings on the camera, next, ok, next, yes, ok, next, next, next, next... kinda got ridiculous so I gave up on the thought of using it very much if at all. Yes, you'll get some pretty decent transfer speeds, but to go through all of that every time just isn't feasible.
The only thing that ethernet port will be handy for is remote shooting/remote control. You could run an ethernet cable for an extremely long distance and still have control of the camera.