The multiplayer aspect is supposed to be a core aspect of the game, no?
I would imagine that's why they're not giving pre-release copies to reviewers, cause didn't they talk about how players could "discover" planets and places and be mentioned as the discoverer. I feel Reviewers would have an unfair advantage in getting themselves tagged on stuff.
Not sure I understand what the fear of spoilers might be, unless the game has some heavier plot element that was previously unmentioned?
Also, since people keep bringing it up - I'm pretty sure review copies of DOOM did not go out because of the reception to that MP beta first and foremost, which honestly was Bethesda's fault for not just having a 1-level demo and then doing it and trying to gain fanfare after the fact.