Was Shakespeare's Ghost Writer ... Shakespeare?

My introduction to the Shakespeare authorship question was Joseph Sobran's 1997 book, Alias Shakespeare. I don't remember much about the book now - except one of the proposed candidates was Christopher Marlowe, who I remembered as the "great reckoning in a little room" guy from The Spell of the Sorcerer's Skull - but I still keep an eye open when stories and theories appear.

Including this April 26 article from CNN:

Columbia University professor and Shakespeare scholar James Shapiro spent 15 years working on his 2005 book, A Year in the Life of William Shakespeare: 1599. The work exhaustively details a key year in the Bard's career, when he wrote "Henry V" and "Julius Caesar" and became the man thought of as history's greatest English-language dramatist.

And yet he couldn't convince the doubters, who believe that the name "William Shakespeare" is a front for the real author.

The result is Shapiro's new book, Contested Will. In it, Shapiro chronicles the history of the anti-Stratfordian movement, which has believed that any number of people -- the essayist Francis Bacon, the nobleman the Earl of Oxford, Walter Raleigh, Christopher Marlowe -- wrote the plays ascribed to the glovemaker's son from Stratford-upon-Avon, born 446 years ago. It's a theory that has attracted some famous minds -- including Mark Twain and Sigmund Freud -- and will soon be coming to the screen as Roland Emmerich's latest film, "Anonymous."

It's a battle that has, as Shapiro records, been filled with partisan rhetoric and bad blood since it began a little more than 200 years ago. Twain, for example, wrote a short book on the subject; his contemporary, Henry James, also questioned Shakespeare's authorship. Others have created elaborate codes or sought biographical parallels. The Stratfordians stand by their proof; the anti-Stratfordians fill in the gaps.