Harry Potter sells 5 million copies on its first day. “That is nearly twice as many as the estimated sales in 12 months of last year’s best-selling novel in hardcover, “The Summons,” by John Grisham.” The book even outsold the weekend’s blockbuster movie. “The five million copies sold, at retail prices from $17 to $30, surpassed the first weekend’s box office for the latest blockbuster movie, ‘Hulk,’ which sold $62.6 million in tickets in its three-day opening weekend.”