Canon Inc: "Video will play a huge role in the EOS R System for sure. For example, an 8K video capable camera is already in our EOS R-series roadmap. And we are not just looking at video from a camera perspective, we are also working on how to make RF lenses better for video capture as well."

Full article: https://www.imaging-resource.com/news/2019/01/08/wheres-canon-going-with-the-eos-r-do-they-have-a-plan

-- peer

Sharp is too:
https://www.cinema5d.com/sharp-8k-micro-four-thirds-camera-teased/