[Brightcolours]

Teaser 1:
It can hinge the display vertically or horizontally. (Is that nicer than a swivelscreen? Probably not?)
https://www.youtube.com/watch?v=u5Fi8f1Py40

Teaser 2: 
It can record 8K 30p for extended periods of time.
https://www.youtube.com/watch?v=q0WF_ExYHD0

[mst]

(Is that nicer than a swivelscreen? Probably not?)

I guess it's more about durability. And should cover typical Z9 use cases (Insta selfies not being on of them)

[Rover]

Eh, the articulated screens aren't for that (at least not primarily). Were you joking, Markus?

[mst]

Partly, yes On the other hand: I can not really imagine use cases for myself where the tilting angles (as we can judge them from the teaser videos) wouldn't do it. I do admit, though, that I rarely rely on the rear LCD instead of the viewfinder... only when I have to.

[Rover]

I remember being instantly fascinated with the articulating screen when I got the Canon 650D. It instantly allowed me to do many things easily, like landscapes and journalistic stuff from odd angles - low and high. The 80D has the same capability but it's better in every other regard. I'm a little envious of the R3 which has both the built-in grip and the articulating screen, thus combining the benefits of the 80D and the 1D series.

[borisbg]

Nikon are quite conservative on these. I am sure you remember how long it took for D8xx to have this. I understand Nikon durability concerns but Oly M1 has had articulated screen since the beginning.

[Brightcolours]

Forgot to post this 3rd teaser:
https://www.youtube.com/watch?v=bJmUe6qdd7M&t=28s

Car/motorcycle/face/eye tracking, with a nice and smooth implementation like Canon does. Not the Sony restless flicker stuff.

[mst]

Looks like some really sticky AF (ok, it's a promo video, so let's wait for some field reports). No substitute for eye-controlled AF, but hey, we can't have everything

[Brightcolours]

Yes, the Canon EOS R3 has that eye-controlled AF selection, but the R3 also has 27.5% less resolution. We can't have everything, indeed ;-)

[mst]

Well, the Z7/D850 already have more resolution than I personally need But no, that's not enough reason to switch back.
I assume a future R1 will have that eye-controlled AF, too. And future lower models also.