Answer by Greg Longmuir:
ROR ranks well not only because it has trust but it is user generated content that is updating by the minute. This is the holy grail of relevancy, if you think about all the content on that site it has to be relevant to much of the search world. Since a "Brand" keyword is less than vital but considered "Relevant" in search engines it ranks high. So think about how Google may interpret a search result, ROR is primarily brand names, so this makes it Relevant, slightly relevant and Useful. 3 of the 5 or 6 classifications I feel search engines follow. There are ways to overcome these posts but it requires committing a dedicated program and seeing it through.