The gist being that React is what happens when a PHP shop creates a client-side framework, with all the architectural warts that this might imply, if you're on the PHP-lowers-the-bar-to-web-programming-too-far bandwagon.
(FB engineers would probably tell you that their variant, Hack, is a far cry from PHP, and their coding standards are well above that of your bargain-basement wordpress drudge, but you get the idea)
> An Application
" Using props and state, we can put together a small Todo application. This example uses state to track the current list of items as well as the text that the user has entered. Although event handlers appear to be rendered inline, they will be collected and implemented using event delegation. "