I think anticipation has a lot to do with suspense. When people hear it was cut to get an R, they think, "Oh well, compromise -- not scary." But when you actually see the film, there was some pretty extreme stuff by the standards of a major studio release.
For those interested, there's a chance to win a free DVD of the unrated version of the film here:
http://hollywoodgothique.bravejournal.com/