NYT: Adcritic.com: A Victim of Its Own Success? (free reg. req.): "Mr. Riley, the AdCritic president, said his site had 500,000 visitors a month and 40,000 registered members who work in the advertising industry. Earlier this year, it began charging agencies to post their material and had signed up more than 100 paying clients, he said. But that was not enough to support the site's daily operation. "Compelling content alone can't change that," Mr. Riley said."