I agree with thylacine, I don't have enough evidence for myself to say where it starts out, because there is alot pointing both ways... DR had quick revive across the map, SNN had it random, Kino was sunny outside so the sky doesn't have too much relevancy to me, and I remember reading somewhere that zombies overran Area 51 and then our 4 buddies went to the moon, but that's what i've heard, I don't know if it was confirmed or if that was a level description or what... Plus in DR pack a punch was right behind where you spawned.
As for it starting on the moon, there is quick revive on the moon (not necessarily in the spawn room if you were to spawn on the moon) and so did all the other black ops maps and this IS a black ops map. Also you can see the PaP in area 51 and in all the BO maps it didn't spawn in the spawn (except for CotD but that varied)
Believe what you wan't, but we will all find out (or at least xbox players will) on the 23rd.