It would be useful to see side by side benchmarking and comparisons of typical Javascript vs React.js. I've just finished reading High Performance Browser Networking, and it appears to me that most client side code is slowed down much more by the network than the language. Am I missing something here? Is Javascript really that bad on its own?
In my experience, JavaScript is quite fast in most browsers. Communication between the DOM and JavaScript is much slower and causing lots of layout invalidation and repaints absolutely kills an app's perceived performance. React's approach is simple for the programmer but takes advantage of the fact that JS is fast and minimizes those slow bits.
