We have been working on major Data migration since last year. So it's a subject we really want to share experience about. A presentation made by Luc in Drupalcamp Manila (Philippines) and titled Drupal を使ったデータ移行について for Drupalcamp Kyoto (Japan).
Luc Bézier's article has been released on the french magazine PHP Solutions. The magazine is dedicated to PHP frameworks. Luc's article is about Drupal and he explain that Drupal is flexible enough to be used as a Framework, like Zend Framework.