This module creates 2 default views for Organic Groups.
1). On a particular group page, recommend other groups that share the same members. That is, "People who joined this group also joined".
2). For a particular user, recommend groups the user might be interested based on the user's own group membership. That is, "Judging by your membership, you might be interested in these groups too"
This module requires the Recommender API module at http://drupal.org/project/recommender. Please see README file for installation details.