It has been confirmed elsewhere that the "hump" will still be there, and for some reason will be at a higher height than the seat base in the 3-row version. That is, the hump will be as high as if you had a 3rd row, but had it folded "flat". Postulate at will, but the most reasonable answer I saw what that they have the cargo tray setup for "leveling" at the levels of: flush with transom, flush with folded seats, in base of compartment. Moving that seems trivial to me, but who knows..
Either way, a 5 seater will still be burdened with the bump in the back, which is why to me, the savings appear to be the only benefit to that configuration.