Drupal 8 Alpha 6 is out and it has a migrate module in there! It even has a few complete migrations: variables to the configuration files owned by system module. Since the last report the configuration of process has changed significantly, this is now documented in the handbook. We have two patches in the core queue, one potpourri of small fixes and one to split migrate into migrate and migrate_drupal, the latter holding the Drupal 6->Drupal 8 and Drupal 7->Drupal 8 migration.