I am looking to install some new features. There are attempts at integrating PHPBB3 and Drupal 7, though it likely won't be ready for prime time until Drupal 8 and PHPBB4 are out. PHPBB4 is supposed to be a complete rebuild.
So I installed http://drupal.org/project/phpbbforum on the Drupal side and phpdrupalbridge http://phpbb.drupalbridge.org/en on the forum side. It's not quite working and documentation is sparse at this stage in the game.
What this integration will do is synchronize the accounts on the drupal side and with the forum. For instance, you would already have an account on the drupal side and you could create a blog, that blog's comments sections would be linked with the forum topic.