“Bestsellers are the books that people who don’t buy books are buying.”

“Delight a critical mass of avid readers. Capture their energy. Let them sell your book.”

“Bestseller tip: People start to read a book because other people are reading it.”

“It’s shared copies that will help create the change you seek in the people around you”
— Seth Godin

http://bookmarketingbestsellers.com/seth-godin-on-the-bestseller-effect/