My wife and sister, both nonreligious, started a book club with about 5 other women.
Most members probably thought the book-club's intent was to read only feel-good books. When it was my wife's turn to suggest a book she offered End Of Faith.
There's about a month between meetings and we heard through the grapevine how some members just hated the book, found it depressing and could not imagine why it was suggested.
The group met at our house. Before discussing the book my wife played Sam Harris' C-Span talk. My wife was happily surprised—the ladies loved him and the book! All agreed, including believers, that religion was at the root of many problems if not evils. Some commented that initially they loathed the book but soon found it's message compelling.
My wife is not sure if any beliefs were changed—that was not her intent—but she felt it was a great first step in having a rational conversation about religion.