Looking at the published photos, there doesn't appear to be a mechanical interface along the edge of the ipad to the stand.
https://www.apple.com/shop/product/MXQT2LL/A/magic-keyboard-...
I've never laid hands on an iPad Pro but photos show it has 3 pogo pads on the backside, is that enough to do data and power? I was under the impression that USB-3 required multiple pairs of data wires. Some sort of proprietary signaling?
Maybe it is using wireless power?
It's the same connector since the new one is backwards compatible with the old iPad Pro.
If you google "iPad Smart Connector pinout" you find previous discussion/speculation on the protocol
edit: the announcement specifically says the stand supports "pass-through charging, keeping the USB-C port on iPad Pro free for accessories including external drives and displays". So the pogo pins only have to have enough data bandwidth to send keystrokes, the stand won't give you USB 3 data
I am a bit confused by the usb-c port for pass through charging. I would have thought a great opportunity would be to have the stand be able to wireless charge the iPad while in use but I expect the power requirements of an iPad in use would exceed current standards.
Regardless, the interesting point to me is with keyboard, pencil, and such, the price point overlap with their laptop line makes we wonder about rumors of an ARM chipped line of Macs. Without the processor difference price comparisons are going to be much more difficult to blow off