Can you trust what you read about Royal Caribbean at online message boards? That’s the question some vacationers are asking this week in the wake of stories suggesting the cruise operator has been manipulating online discussions for more than a year. Veteran industry watcher Anita Dunham-Potter of ExpertCruiser.com first broke the story last week, reporting that Royal Caribbean has been rewarding a small group of fans who post positive comments about the line at sites such as Cruise Critic with free cruises and other perks. Dunham-Potter’s story, which since has been followed by several blogs and news outlets including The Consumerist, notes that the group — called the Royal Champions — has been active since 2007.