So, if you have missed it, Drupal 7 is stable (it has been since the start of January), and this means that more and more people are going to be looking at Drupal 7 both now an in the future to work as their content management system. Much of the work I do involves either migrating sites from other formats (CMSs, static sites or bespoke sites) into Drupal or importing of other data into Drupal to open the data to Drupals awesome data management and processing.
Therefore it is important to look at how Drupal 7 imports data so that you can take data and place it in Drupal. For Drupal 6, http://www.lullabot.com/articles/drupal-data-imports-migrate-and-table-wizard,you can use the migrate module and the migrate ui to import data, however, for Drupal 7 migrate has been re-written and the UI has been disposed of and in its place solely Drush integration for migrating your data.
What does this mean for regular users and migrating data. Well if anything it makes the idea and practice of migrating or importing data to Drupal 7 more complex, and probably less user friendly due to the lack of UI. However, with the improvements and additions, such as natural adding of node, term, user and many more, potentially it will enable far easier migration.