Grants talk:IdeaLab/Allow users to rank articles on usefulness
1. What do you need that - a "way to identify authors or groups of authors producing meaningful content"? Suppose author A produced content that was rated higher than content produced by author B. So what?
2. Rating of something makes sense if you need help while choosing one item of many. For instance, you want to choose one smart phone of many available, or one app of many apps for the same purpose. In Wikipedia there is a single article for each topic. If there were 100 articles about Apple, then rating could help to identify the better one. There is a single article about Apple. Rating makes therefore no sense.
3. The quality of ranking systems on the most web sites is poor. Let's look at Play Store. The most ratings have no comments at all or comments are useless like "Cool", "I like it", "Great app". Many users complain about many points, this sounds like 1 star, but despite complains they still give 4 or 5 points. Means, even ranking with detailed feedback can be useless.