I believe the real reason is manufacturing cost. A lot of people, myself included, whinge about the form factor and those utterly stupid rubber I/O covers and the battery configuration, let's face it, you have to use the battery grip to get acceptable run time, or an external battery option. Blackmagic know this, but it's cheaper to slap some minor improvements in an old design, than it is to build an entirely new camera. I'll come back to Blackmagic when they have a Red / Arri / Z-Cam / Kinefinity modular box design. Mark my words, they'll kill it when they do, because they'll offer all the necessary components (nose to tail) for more integrated experience than Z-Cam and Kinefinity, at a much more attractive pricepoint and with BRaw/Resolve to seal the deal. Hurry up and build the BMCBC!