WordPress.com and App for Mac

Did WordPress just translate itself to node.js?
Big question, will they also open-source this code-base for users to host on their own sites? If so, this is probably the beginning of the end for PHP? WP is certainly the only PHP application I run. And probably the most widely used PHP program in the wild. (Not counting FB here.)
If they aren’t going to open-source it, is this the beginning of the end for WordPress as the world’s most popular Open Source social-software? Is WordPress.com going to try to turn itself into a more closed, “gated” community? With new features only available to users hosting within it? Is it going to become more like Tumblr … or Medium or even FB?
Update : It’s all open-sourced.