• http://www.naturalsearchblog.com Silver

    Users tend to rate/review things which they have more of an emotional response to, whether it be positive or negative, I think.

    Users typically feel more strongly about Movies for instance, and are more likely to rate them than something like Car Inspection businesses.

    Restaurants, which engage emotional response through visual sense and through the sense of taste achieve a greater response from Gas Stations, as another example.

    Your question on whether users will go rate something at multiple different sites is interesting. I think they’d be more inclined to rate stuff at a site they consider to be the main/authoritative one for the subject matter.