Seems a new theory has been put forward by a dood from my own hood:
http://forum.casebook.org/showthread.php?p=77337
Assuming this is true, does it matter? Hasn't J the R, the legend, far-outstripped J the R, the person? Why is it that 120 years later, he's still such an object of fascination to so many? Was he the first recorded serial killer? What was so special about him that he's still a household name today? Any thoughts?