Last night I presented the following slides at the Ansible St. Louis meetup at Riot Games. In the presentation, I mention the motivation behind Ansible and Galaxy 2, and run through most of the major changes and new features:
I've incorporated many of the new features in Ansible 2.0 in my book, Ansible for DevOps, and will be rewriting a few of the examples in the book to take advantage of new features in Ansible 2 soon!