Credibility on the internet: shifting from authority to reliability
R. David Lankes

Great article on how credibility is created, lost and used on the internet. Cites really good sources.

http://www.emeraldinsight.com/Insight/viewContentItem.do;jsessionid=229D0A3004DFD5AE6C0D61611233DD0E?contentType=Article&contentId=1745106