In an update to Amazon Reviews: More than Meets the Eye, I received an email from fellow author Ann Douglas. Canadian Ann is an active and successful writer of 28 books on pregnancies, babies, and parenting. Ann has thoroughly researched this issue and has a page of links regarding the situation on del.i.cious.
Earlier this year, I had discovered a disturbing pattern of negative "prank" or false reviews on Amazon.com, and they seemed mostly directed at writers of color. I found reviews that followed a similar pattern on the Amazon.com sales pages of books written by writers including Ralph Wiley, Toni Morrison, and Octavia Butler. I also found this type of review aimed at female writers as well -- and have heard fellow female SF/F writers mention this issue for years.
One might think that people would learn what a negative and useless activity this is. One might be wrong. I could be wrong -- but I think the particular activity I've discovered is primarily aimed at writers of color, female writers, and - likely - GLTB writers as well. Admittedly, this is a sampling of one, but I previously saw zero activity of this type with male SF/F writers (though as I said, it's common for female writers to receive deliberate "drive by" reviews by people who obviously hadn't read the books). One might think Stephen King would attract this type of attention too -- by pranksters, resentful "fans" and so-on. He only wrote a whole book about a "fan" who thought she could do better! One might be wrong. Sorted in reverse, his lower-rated reviews seem to all be legitimately people who didn't care for the book. And there weren't that many of them.