Vanity Fair’s mogul watcher Michael Wolff caught a very big fish, signing a “high six-figure deal” with Doubleday to chronicle the rise of News Corp. chief Rupert Murdoch from his early days in an Australian newsroom to the helm of a global media empire.

The book is supposed to come out in the fall of 2009, plenty of time for Wolff to collect all the juicy details about Murdoch’s bid for Wall Street Journal publisher Dow Jones. Wolff’s last book “Autumn of the Moguls” was published by Murdoch’s own HarperCollins imprint, but the columnist turned to other houses to shop their boss’s bio.

Based on the press surrounding the deal, some of the cozier elements have not escaped notice.

“It’s a biography of Rupert Murdoch — the last mogul who really understands how his business works,” Phyllis Grann, the senior editor at Doubleday who is assigned to the book told Murdoch’s New York Post.

Publisher’s Weekly noted that Murdoch has agreed to cooperate with the account of his personal history and provide access to his friends in business and family, though it is not an “official” biography.

Columbia Journalism Review went a step further, saying Wolff’s recent profile of Murdoch in VF (Sub-headline: “The man who terrorized a generation of journalists may be the last mogul standing who truly loves print”) was not only the media equivalent of Botox when it comes to beautifying his record with journalistic integrity, but “had ‘book proposal’ stamped all over it.”

“I’m confident that as Wolff tucks into his explication of the tragically misunderstood Mr. Murdoch, he will give Rupert no cause to regret his decision,” wrote CJR’s Brent Cunningham.

We’re ironing and starching our hankies for a good weep.