Washingtonpost.com today published a follow-up story to the pieces we ran last week on the unplugging of a California Web hosting company and the subsequent worldwide drop in spam levels. Today’s piece tries to answer the question we heard from so many readers: “How Can So Much Spam Come From One Place?” Some of the less newsy but just as interesting stuff was cut from the piece for space and story flow reasons. One of those was a section on what security experts think the incident will mean for the evolution of botnet technology and its use by the bad guys: Security experts worry that botnet creators will learn from the experience and make key changes to improve the security, stealth and resiliency of their herds. One of the largest and most advanced spam botnets ever designed, “Storm,” was successful in large part due to its decentralized nature. As the