Olympus made an official statement that they are working on a new pro body for Four Thirds lenses:
Olympus working on new body for top-pro lenses
Akira Watanabe, manager of Olympus Imaging's SLR planning department, confirmed today that the company is definitely working on a body to deliver the focusing performance expected by users of the Top Pro lens series like the ground breaking 90-250 f2.8 fixed aperture zoom.
Watanabe has been delighted with the success of the OM-D which has pushed the boundaries of performance for system cameras but acknowledged that it did not deliver with the legacy high end lenses from the E-System. Whilst further information wasn't forthcoming, he was keen to emphasise that Olympus is actively developing a solution and will announce more details in due course.