Update Ecosystem.md

Author: gaearon

docs/introduction/Ecosystem.md

@@ -32,6 +32,7 @@ On this page we will only feature a few of them that the Redux maintainers have
 
 * [Live React: Hot Reloading and Time Travel](http://youtube.com/watch?v=xsSnOQynTHs) — See how constraints enforced by Redux make hot reloading with time travel easy
 * [Cleaning the Tar: Using React within the Firefox Developer Tools](https://www.youtube.com/watch?v=qUlRpybs7_c) — Learn how to gradually migrate existing MVC applications to Redux
+* [Redux: Simplifying Application State](https://www.youtube.com/watch?v=okdC5gcD-dM) — An intro to Redux architecture
 
 ## Using Redux