Drupal 7.10, a maintenance release with numerous bug fixes (no security fixes) is now available for download. Several major bugs, including one causing errors with the 5.x branch of Drush, have been fixed this release. See the Drupal 7.10 release notes for a full listing.
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.