In a recent interview with Focus Numerique Olympus executives revealed that image sensor with 8K video support will be coming to future Micro Four Third cameras:
“We can assure you that there is no problem in developing sensors at 33 million pixels for filming in 8K. We started the 4/3″ saga with a sensor at 5 Mpx In 2003. Now the same sensor is at 20 Mpx with a much higher image quality especially for the management of electronic noise.”
Olympus also mentioned a Bluetooth-based app (similar to Nikon's SnapBridge) and handheld high-resolution image mode could also be implemented in future camera models.
Panasonic has also been talking about 8k video for a while: their initial plan was for 2020, then it was pushed to 2018.