Most Prolific Author

Who is the world's most prolific author? Glancing at my bookcase, I would have guessed easily Stephen King. I have all of DIckens' novels, but they only take one shelf -- and not even all of the shelf. While Kings work takes five shelves and I don't own all of his work. But, I'm worg! Stephen King is not the most prolific author. . .

• Philip M. Parker. Well. . . sort of. He has invented a machine that collects information and generates books. Like, uh, 200,000 of them. http://www.nytimes.com/2008/04/14/business/media/14link.html
• Isaac Asimov wrote over 250 books. http://www.snarkout.org/archives/2002/06/14/
• Mary Faulkner was credited by Guinness Book of World Records as having written 904 books. She was a South African writer wo wrote under si pen names. She died the year I was born. http://www.funtrivia.com/askft/Question105055.html
• John Creasey pubished over 600 novels. Strange, he also died the year I was born. http://en.wikipedia.org/wiki/John_Creasey

This begs the question: Just how many books has King written? About 54. Depends on what gets counted: Novels only? Short story collectons? What about Silver Bullet? Do popup books count? How about comic books -- sorry, I mean graphic novels. What is impressive about King is not simply the number of books written, but the variation.