Having seen the film might taint my judgment and enjoyment of this novel, and certainly cut any factor of suspense. Despite that, I did enjoy the book, partly for it's look at my neighborhood, New York City's Upper West Side, in the mid 1960s. Although in 2010 it's much harder to see witches as evil satanists rather than good-hearted New Age Pagans than it would have been when it was published in 1967, the book doesn't feel dated.
I think this is one of the cases where the film is better than the book, which is not to say the book is mediocre, just that the film is excellent and deftly captures the book so well, I was constantly reminded of the film while reading. The book conjures up its time and place very well, and Rosemary, the young wife and mother-to-be of an up and coming actor makes a very good Everywoman. The style and pacing is so smooth, it seemed a minute from opening the book I was looking up blinking, five hours had passed and the book was finished. A good read, even if not the kind I'd keep on my bookshelf or ever reread, or one that touched me emotionally or intellectually.