At 38:00 in the clip they Audyssey guy starts talking about a special cable to adapt the old Pro kit to the AVR, and is inserted between the preamp and the AVR. The cable can be long, up to one km. Price and when available not decided yet, but prototypes have been made and tested.
Can't use an USB mic as it needs to be connected to the mic input on the AVR, but they plan to release individually calibrated mics that are not as expensive as the old Pro kit mic and is more consumer friendly. Price and availability to be decided.
Nothing said in the clip (or I missed it) about using my own audio interface where I can route the mic in to analog out and thus use my own measurement microphone.
@Kal Rubinson posted earlier that he asked that question in the session but did not receive an answer.
Currently this appears to be a Windows app with improved UI (non-touch editor of PEQ), some smaller changes, but not that much different than the Android/iOS app available for a tenth of the price and without the new onerous licensing scheme.
It's commendable that an app like this is released at all, but I think I'll wait with upgrading my 2015 model Denon AVR-X4200W that does not support the Android/iOS app nor, of course, the new Windows app. Use of my own measurement mic would make me reconsider, though.