Drupal 7.5, a maintenance release which fixes security vulnerabilities is now available for download. Drupal 7.7 also fixes other issues reported through the bug tracking system.
Note: Drupal 7.7 is just Drupal 7.6 with a fixed VERSION string (7.6 was reporting itself as 7.5). No other changes.
Upgrading your existing Drupal 7 sites is strongly recommended. There are no new features in these releases. For more information about the Drupal 7.x release series, consult the Drupal 7.0 release announcement.