The behind the scenes at Amazon's customer reviews are chronicled at Slate.
"I suppose I shouldn't have been surprised, but I had imagined Amazon's customer reviews as a refuge from the machinations of the publishing industry: "an intelligent and articulate conversation ... conducted by a group of disinterested, disembodied spirits," as James Marcus, a former editor at the company, wrote in his memoir, Amazonia: Five Years at the Epicenter of the Dot.Com Juggernaut. Indeed, with customers unseating salaried employees like Marcus as the company's leading content producers, Amazon had been hailed as a harbinger of "Web 2.0"—an ideal realm where user-generated consensus trumps the bankrupt pieties of experts. As I explored the murky understory of Amazon's reviewer rankings, however, I came to see the real Web 2.0 as a tangle of hidden agendas—one in which the disinterested amateur may be an endangered species."
The author alleges "that Grady Harp's 92,000 "helpful votes" are the product of collusion—that Amazon reviewers often strike e-mail bargains to "yes" one another's reviews."
For what it's worth, independent bookstores are, well independent. As in not beholden to publishers or anyone.
Posted by Dave