If Olympus leaves the MFT group there will be only 43 companies left supporting Micro Four Thirds :)

Now, obviously Olympus stepping out of the MFT world is a major blow. Still, the MFT group is officially supported by 43 companies (outside Olympus). Most of them have other interests (security or astro cams) some of them never made a MFT products (Fujifilm). The only relevant camera makers are Panasonic, maybe Sharp (if they make that damn 8K MFT camera) and of course JIP (if they decide to make new cameras).