That’s what I wanted to know when my publisher used that phrase. As it turns out, a "book trailer" is only the latest way of introducing the webby, Youtubey crowd to books. It’s like a "trailer" or a "coming attraction" for a new movie, only for a new book. Like movie trailers, they’re short little films with music and captions and voiceovers. Take a look and see what you think about this one, which stars Sam Rockwell, Liza Colon-Zayas and an increasingly old Jesuit priest. Anyway, see what you think about the latest trend: