Content that consumers leave on an ecommerce site can improve the site’s search engine optimization, if the platforms and underlying code are set up optimally. Ratings, reviews and comments each play a part in SEO, utilizing the words and opinions that real shoppers voice to strengthen optimization.

In aggregate, these types of content fall under the label of user-generated content. I wrote in more detail about reviews and SEO here, in "SEO: Letting Customers Generate Long Tail Search Terms." The gist of that article still stands. Optimizing a site manually for the millions of phrases that could drive one or two converting customers just isn't scalable. User generated content such as reviews and question-and-answer sections can solve t...