Nikon has announced that it's developing the Z9, a flagship full-frame mirrorless Z mount model with "the best still and video performance in Nikon history." The new model will be released in 2021 with 8K video and other advanced features.
Nikon said that the Z9 will have a "newly developed FX-format stacked CMOS sensor," likely in the 40- to 50-megapixel range. It will also feature a new image-processing engine that will be necessary if it wants to keep up with Sony and Canon in terms of shooting speeds an autofocus/eye-tracking performance. The image shows a built-in camera grip, much like the $6,500 D6, meaning you wouldn't need to buy a separate one as with Canon's latest EOS R5 and the Sony A7S III.
Besides 8K video, Nikon said the Z9 will offer "other video specifications that fulfill diverse needs and workflows." That likely means you can expect 10-bit or even RAW internal video recording, along with a generous range of 4K resolutions and frame rates.
The news isn't a great surprise, as I mentioned the possibility of a new Nikon flagship with 8K video in my review of the company's current top-end mirrorless model, the Z7 II. Nikon has been lagging behind Canon and Sony in terms of technology with its full-frame cameras, so hopefully the Z9 will bring it up to par, at least. There's no word yet on pricing, but Nikon has promised more information in the months to come.