I have a couple of SMF forum sites I wan't to replace with Drupal, but there is a considerable amount of content, why I started to speculate if it could be done programmatically (semi automatic magic). I found a couple of outdated modules for merging data from SMF to PHPBB and then from PHPBB to Drupal. I tried that route once but did not succeed. The thing I would love to see is a transformation of the table data in the SMF database to CSV and then import it with the standard import module for Drupal Migrate. I think that a good Content Management System (CMS) should include a good standard export of the content. This must be great for marketing too - if you don't like it it is easy to get your data to a different platform.