Many do believe the new Canon and Nikon Full Frame mirrorless system will start a new “Mirrorless War”. And in a time where the digital system camera market has become a niche this might be dangerous for Olympus and Panasonic. According to Tony Northrup both Olympus and Panasonic will face a seriously challenging time and they will struggle to compete if they don’t evolve.
Just my two cent: In my opinion the Nikon and Canon systems will play in the high league only (in terms of price and audience target). And I think this is actually good news for the smaller sensor and cheaper systems. They will not have a direct competition from Canon and Nikon. A Panasonic G9 costs 3-4 times less than a Sony A9. It’s not Full Frame granted but the speed is about the same. Not everyone has $2000 or more to spend on a camera and not everyone wants big lenses. I think MFT and the Fuji X system will enjoy the bloodshell FF fight between Sony-Canon-Nikon FF systems from the distance :)