Here's the abstract for an interesting article that is published in the journal Business Insurance. You'll have to pay to obtain access to this article, or you can get it through a library.
Abstract: The article delves into the risks beneath the use of social media outlets by companies. Experts revealed that the risks firms may be facing are categorized to information technology and reputation, while concerns can be in the legal form with defamation and copyright risks and in the workplace productivity, when employees are engrossed to using social networking sites. Robert Stroud of the Information Systems Audit & Control Association advises firms to search the Web about their brand to prevent harmful information on social media forums.
Here's the permalink: http://www.businessinsurance.com/article/20100912/ISSUE03/309129997
Of course, a private investigator can help you monitor your reputation and obtain useful intelligence on those who are undermining it. Feel free to get in touch with Claude if you have questions about various countermeasures.