James Fallows passes on a reader's theory that advertising revenues are plunging because advertisers have figured out that advertising doesn't work. This makes no sense to me. Advertisers are not moving ads from newspapers to Craigslist because advertising doesn't work, they are moving ads because Craigslist is a better way of distributing ads. Newspapers are in trouble because the internet has made physically printing and distributing a newspaper increasingly cost ineffective. Advertising will change but there will always be a need for ways for people with things to sell to communicate with potential buyers.