You think they will ever go down the wireless route? I suspect it's like 30mm crank axles.. I only hope the do go down the 12 speed di2 route soon enough..
Just get your di2 wires hidden in your frame, you'll never need to replace them like normal shifter cables.
Perhaps. When Shimano go wireless I'll give it a go.
On a slightly separate note, I did wonder if there might be a chip in it that would record failed shifts?