So this is cool. The Commerce guys and Microsoft teamed up and got a php pdo driver to work. The Commerce guys will be maintaining the Microsoft database integration module in contrib repo. It means that it becomes accessible to a much broader audience. People will be able to use native windows backup tools to backup their site databases. Deploy on a server platform they are familiar with.
This opens up Drupal to a whole new audience that previously would not explore using Drupal at all. It will be interesting to see what things people have not previously considered that this group will bring to the community.
Microsoft announcement here