Viewing a lot of Youtube videos with James Randi, he is knowledgeable, and highly entertaining. He knows how to deliver a lecture or an interview in an engaging manner.
I hoped for a deeper book. It offers a lexical dictionarry with a very laconic description of each issue. Sometimes the information is wrong. For example, under the value "Kabalah" he gives the description of only a relatively minor stream of the Kabalah, as if it was THE definition of Kabalah. I think that most people who believe in Kabalah are not part of this stream, and thus they would disagree with this definition.
As of today, it is easier to get better information about each term, from the Internet, than looking at this rather boring and inaccurate Encyclopedia.