When they talk about radiant ai in that interview they keep on talking about "1500" npc's.
So they gave it a 500 boost?

sounds more like they rounded it up a little, while they rounded it down first.
Theta and switch: Yes i found the music a bit Pirates of the caribean/lord of the rings like too.
It could be that the good old morrowind music is still in it. In that 20 minute gameplay movie, at the start just before they press new game, you hear the morrowind theme. Ofcourse it's 6 months old (or even older) so it could be they just used it because they didn't have anything else yet, and that they'll replace it with this new song now.