http://www.redsharknews.com/technolo…-frame-4k-dslr
The short of it is that Sony have announced that if you have an F5 it is now fully upgradable to F55 spec.
In other news both Blackmagic and AJA have announced new cameras. The Blackmagic URSA looks particularly interesting with user swappable sensors and a more ENG style form factor (though you need to add a viewfinder to use it that way.
The URSA can be configured with a S35 sensor, or with a B4 mount with ND filters and a ⅔" sensor. With the way you can swap the sensor it will be possible for you to have a S35 sensor for some jobs, then swap it out for the B4 ⅔" sensor for ENG style work. Ingenious. The price is $6k.