Apache Roller 5.0 is an open-source Java blog server used by notable entities such as Sun Microsystems and IBM, offering features like multi-blog support and integration with LDAP. The document outlines the development history of Roller, highlighting significant milestones and new features in version 5.0, such as OpenID support and media blogging enhancements. The project seeks community involvement to ensure its longevity and address ongoing needs in maintenance and feature expansion.