Just went to read the change you were talking about. Yeah, I guess it works well enough to the same effect without needing as much buildup, and being a little more believeable.
Still, I don't think there was anything wrong with the original ending. I don't think it is that far out there, plenty of people believe in aliens, and you have plenty of conspiracy nuts out there who claim the US goverment is planning on pulling pretty close to the exact same thing Ozy Mandias did and for the exact same reason. I think the original ending would have worked well enough, but I don't think I really mind this minor departure and simplification too much.