Often shoppers judge books by their covers, at least at first glance. Reading some of my favorite authors happened by chance as I picked up one of their books based upon the cover. Steven Brust's early novel Jhereg, is one example. This book came out when I was 13 - it was about an assassin witch. I loved the art work so much I used the font from the cover of this and others in the series to create the designs for one of my tattoos. Another book I picked up to look at just because of its cover was Orphanage by Robert Buettner; first published in 2004 it had a great retro Sci-Fi feel, and it reminded me of many of the early covers of Robert A. Heinlein's books, and in reading the cover I found out it was written in homage to Heinlein's classic Starship Troopers, which is an amazing commentary on war. So of course I had to buy it that very day. 
Third, The Dark Hills Divide by Patrick Carman, had something mystical about the cover and it had an effect upon me. I had the book for almost two years before reading it because I did not want the spell of the cover to be broken.In years gone by I collected every edition of different books. Some of Piers Anthony's books have gone through 5 or 6 cover changes. Many classic science fiction books were originally only available in pulp, paperback editions - cheap to make and cheap to recycle to make new ones. I owned the complete Edgar Rice Burrows Warlord of Mars series originally published between 1917 and 1964. These books were transformational in the years after I first learned how to read. Let me digress for a minute. With a dual form of dyslexia and after repeating grade one, they just kept passing me on in school. I got through my book reports by renting VHS or
Beta tapes, and paying close attention in class. The summer between grades seven and eight I was sent to a private summer school, and I went from reading at a grade 3 level to reading at a university level and reading over 400 words per minute. It was this whole world that opened up to me that I never knew existed. Reading became an addiction and books an obsession. I read many DAW books, a publishing company dedicated to Science Fiction books. At the time of their merger with Penguin Group in 2007 they had published 1400 books, and from the inception in 1972 until 1985 their books all had yellow spines and a yellow logo box on the front cover. Therefore as you browsed used book stores you could easily recognize the books even if they were not cover facing.
I am sure that you are aware that a great deal of planning goes into choosing covers for books. Publishers also change covers if a book has been out a while, if response was not what was expected. A few years back a book called The Traveler by John Twelve Hawks came out, in the original prereleases of the book there was no author or title on the front cover. But eventually the American arm of the publisher forces a small black diamond with this info. Later they changed the cover completely so that the title and author was in large blocks on the cover. I personally was more attracted to the original, it was so unique and different it immediately grabbed my attention. I often judge books by their cover, or if I do not know the author their covers induce me to pick up the book or to leave it on the shelf or table. It is all part of how books are marketed to us. The next time you are in a Chapters or Indigo books, check out the tables, check out the books on the end caps of the bookcases. These spaces are rented or sold to publishers. Some tables will be all books by one publisher, some will be thematic or issue focused. But most of these books on tables are there to get your attention, to inspire you to pick it up and hopefully purchase it. 
Another thing used to draw you to certain titles are book lists. At Chapters you receive a discount on the Globe and Mail best sellers' list, and then there is Heather's Picks. The owner of Chapters-Indigo has a table with her selection of books that influence her and are favorites. The other is Oprah's Picks - the day a book is mentioned on her show most Chapters, Indigos and Coles in Canada sell out. The stores start getting calls to reserve them before the show has finished airing. There is an interesting story about Canadian author David Adams Richards. One of his books was selected to be an Oprah Pick. When his publisher told him this, and that it would dramatically increase sales, he went to look at this list of Oprah's Picks. When he saw the books on the list he did not want his name associated with those other books and opted not to allow his book to be one of her picks. Yet all of these marketing tricks are designed to get you to pick up the book and hold it, In part to judge it by it's cover.
Seldom when book covers change do I appreciate it. I am a creature of habit and like things to stay the same. A few books that have changed the cover art for the worst, in my opinion, are Dust by Arthur Slade, Fidelis by A.R. Horvath, and Speak by Laurie Halse Anderson. Some books that have pulled it off well are Orphanage by Robert Buettner, The Singer by Calvin Miller and Night by Elie Wiesel. So drop me a line and let me know what books you have judged by their covers and whether it was worth it. Yet all in all judging books by their covers has almost always served me well. Seldom have I been terribly disappointed and wished I had not read the book. So as you look at that next book cover, and its placement in the store, consider all the factors in the marketing behind it, before picking it up, flipping it over and reading the back. Yet as always remember you never know what you will find between the covers.(First Published in Imprint 2009-05-29.)
