In this excerpt from the Learning Forward publication, Powerful Designs for Professional Learning, the author provides a helpful overview of the presence and role of social media in the context of professional learning opportunities. The article presents the idea of the "Networked Teacher" and how educators can leverage tools like microblogging, PLNs, chats, Twitter, and more to create a more cohesive approach to professional learning. The excerpt also does a nice job of discussing the advantages of connectivism and its impact on learning.
https://learningforward.org/docs/default-source/docs/powerful-designs-chapter20-social-media.pdf