The “Read Alikes” recommendations supplement our existing automatic and member recommendations. “Read Alikes” are based directly on the members who have your books—the people who “read alike” you, or whatever.
So far, opinion is divided. Some members love it, and are getting great recommendations. Others report a parade of things they already know about. Is it quite consciously, however, a beta feature. It may be improved, or it may go away. Most likely, it will go away and be replaced by a better overall algorithm, with better tools for managing your recommendations.