Actually I think it will be a standard keyboard with buttons and screen, to which you will plug in a USB Stick with the type of keyboard you require, (Arranger/Workstation/Organ etc) the USB stick being the equivalent of a Removable Hard Drive. (So no OS or software to load as it is already on the USB Stick, also no moving parts)
Whether it will be an open system or manufacture specific remains to be seen.
Enjoy whatever you play

Bill