Update broken link in 'why react' article

_posts/2013-06-05-why-react.md

@@ -31,8 +31,8 @@ to render views, which we see as an advantage over templates for a few reasons:
   **no manual string concatenation** and therefore less surface area for XSS
   vulnerabilities.
 
-We've also created [JSX](http://facebook.github.io/react/docs/syntax.html), an optional
+We've also created [JSX](/react/docs/jsx-in-depth.html), an optional syntax
-syntax extension, in case you prefer the readability of HTML to raw JavaScript.
+extension, in case you prefer the readability of HTML to raw JavaScript.
 
 ## Reactive updates are dead simple.