In 1977, former member of the Vatican noble guard Franco Bellegrandi wrote a book called "NikitaRoncalli" on John XXIII and the 1958 Conclave, revealing some juicy details that caused quite a stir. I think it was not published in Italian until 1994. The name "Nikita" seems to be an allusion to Communist Nikita Krushchev.
An English translation is now available for free PDF download here:
http://www.huttongibson.com/PDFs/huttongibson_NIKITARONCALLI_book.pdfHas anybody read this book yet? Seems that the pivotal event that caused the mess of the last 50 years is the 1958 conclave.