A questão da confiança (trust/trustworthiness) é muito mais difícil em relação aos dados do que ao serviço prestado. Um artigo muito interessante relacionado com isso (e infelizmente não apenas sobre os dados fornecidos por sistemas informáticos):
Wikipedia hoax points to limits of journalists' research
A sociology student placed a fake quote on Wikipedia, only to see it show up in prominent newspapers, revealing that a lot of the press doesn't go much further than most 'Net users when it comes to researching a story.
"Fitzgerald was apparently curious how far his hoax would spread, and expected it to appear on a variety of blogs and similar sites. Instead, to his surprise, a search picked it up in articles that appeared at a variety of newspapers. Fitzgerald eventually removed his own fabricated quote and notified a variety of news outlets that they had been tricked, but not all of them have apparently seen fit to publish corrections or to ensure that their original stories were accurate, even though fixing a webpage shouldn't be a challenging thing.