Wonderful book. Best I've read in over 6 months. I simply devoured the 1000+ pages in less than a week. The only thing that annoyed me, is that at the end it turned out that The Passage is only the first book in what is - hopefully - to become a series... and the second book isn't published yet!
I bought The Passage to try out the horror genre, but it turned out to be more of an epic story, combined with horror-elements. It absolutely worked for me. Highly recommended!