Twitter is expanding its advertising program to show ads to users who didn’t take some direct action to trigger them, either by following a specific account or searching for a term on the service, Peter Kafka reports. Until now, advertisers could place in-stream messages before users who already had chosen to follow them. The new program lets brands reach users whom Twitter judges to be similar to others who follow the brand. The ads will appear on starting in September, and Twitter users cannot opt out. The move is part of Twitter's quest to begin profiting from its large network, but like other recent attempts it may bother some users. || Earlier: Twitter charges $120,000 a day for promoted trends