Close observers of Amazon.com noticed something peculiar this week: the company's Canadian site had suddenly revealed the identities of thousands of people who had anonymously posted book reviews on the United States site under signatures like 'a reader from New York.'

The weeklong glitch, which Amazon fixed after outed reviewers complained, provided a rare glimpse at how writers and readers are wielding the online reviews as a tool to promote or pan a book -- when they think no one is watching.

...

Under Amazon's system, any user may submit a review without publicly providing any personal information (or evidence of having read the book). The posting of real names on the Canadian site was for many a reminder that anonymity on the Internet is seldom a sure thing.

...

CLB: There are two issues here: an anonymity violation; and the problem of pseudononymous self-reviewing - a war of reviewers if you will.