First off, Horgan is a journalist who knows his craft.  In most recent work he has taken to exploring the vast frontier of consciousness and spirituality from an “outsider” perspective.  This is his attempt to make sense of all the confusion and often conflicting reports.  It is funny, witty, and engaging.  One of my only reservations is his tendency to, when he is up against a philosophical wall, take the pragmatic approach (that is, he relies upon his direct experience with the personality from where the information is coming from rather than taking the information and the personality as two seperate things.) 

I wouldn't rely upon it for my philosophical arguments but it is still a great read.