They've already got several major orders. It'll be a viable alternative to the limited capability of the Herc (due to its internal dimensions) and the very expensive C-17 (how many airforces have been able to afford that?). Completely new airframe, modern avionics, new engines: shouldn't be too bad...
What Charlie said. This isnt a new idea, they have been designing it for quiet a few years now, and will be very sucessful. As Charlie said, its a very good inbetween of the C17 and Herc. Looks like an Airbus cockpit to me, the screens are a little bigger for military requirements, but the same standard layout and side-stick.
As for it being a copy of some antanov or whatever, maybe, but its also a basic copy of the C130 which is god knows how old. No point going down that road, as the designs for such transports will be pretty much the same, as its the best method. High wing 4 prop. change the tail a little there ya go.