Just a reminder that by the time you read this, the book called A Royal Duty by Paul Burrell, who for a decade before her death was Princess Diana's butler and close confidante, will be in the stores. Kept under wraps until the last moment by the Penguin Group for security reasons, Burrell's book was signed some months ago by Putnam president Carole Baron for world English rights with Curtis Brown agent Ali Gunn. In it, according to the tabloids, Burrell will offer letters from Diana showing that she feared her car might be tampered with (in fact, a car crash killed her in Paris six years ago) and that her father-in-law, the Duke of Edinburgh, disapproved of the affairs both she and Prince Charles were having.