Photo Rumors hears the two shooters will switch to a newer, faster hybrid (both contrast and phase detection) focusing system that also includes Sony NEX-style manual focuspeaking, which provides a rough visual guide as to when a subject is as sharp as possible.
Other refinements include a MF Assist function that magnifies a portion of the image while framing to simplify fine focus adjustments, as well as a Peaking function that highlights sharply-focused areas of the image on screen.