Acquia, who provides products, services, and technical support for Drupal, has reported that there will be a new and improved migration process for Drupal 8. This migration process will affect those looking to upgrade from both Drupal 6 and Drupal 7.
This change was brought about due to an outdated use of update.php and the hook_update_N() function. It seems that it worked well for basic sites but not so well for more advanced sites. To this end, users had switched over to the Migrate module for the major version updates.
The Migrate module allows the users to create a new site and customize its configuration. This way they are free to change the architecture. It also allows for the swapping out of older, antiquated modules for newer updated ones in Drupal 8. This can be accomplished either via a web form located in the admin or via Drush.