Since Oceania's Mariner is listed as 1,260 berths, I would think that the 629 refers to cabins.
Thus the Regent 450 would refer to cabins. At 2 berths per cabin that would equal 900 folks at 2 per cabin. But previous Regent statements said there would be some single cabins. Thus, that would put pax capacity in the 800-850 range of previous statements. And yes, Regent reportedly has said that the standard double suites would be larger and the single suites about the same size as Voyagers standard cabins.
