[pertinent link] ... but who knew it could be so shamelessly lucrative on an individual level.
I am sometimes asked to mirror my reviews on certain e-commerce sites, but I always refuse. In addition to practical concerns (e.g. unsurprisingly, I prefer to retain ownership of my own reviews), I simply do not wish to be part of star-rating systems that can be so easily manipulated and are so non-reflective of serious thought.
The only rating system that I've ever found appropriately judicious is the Internet Movie Database's ten-point system [Rotten Tomatoes was pretty good until they badly redesigned a perfectly fine site and ruined it]. Why it works so well for IMDb, I have no idea, but the astounding degree to which the individual ratings conform to my own highly diverse tastes and viewing experiences comprises a large part of the reason why it is my favorite website to frequent.