The javascript language is used routinely in the Internet, but compared to other programming language the public awareness is a clumsy. A detailed look into node.js shows that it's surprisingly powerful concept. According to Stackoverflow, it outperforms the C language easily, https://stackoverflow.com/questions/27432973/why-is-this-nodejs-2x-faster-than-native-c/30058978
And it outperforms also old school website programming tools like PHP. The wordpress software is the most widespread blogging software in the world. A possible replacement, called Ghost, was written in node.js and according to the user it's easier to install and has a better performance. So let us analyze the facts: Node.js is better than C, and node.js is better than PHP. Does this mean, that both languages are obsolete? It's to early to answer the question, but it seems, that the project should be taken seriously.
A possible approach to replace a python gui app with node js is described here https://www.npmjs.com/package/node-gtk#example it is based on the node-gtk library and the sourcecode for the hello world app is only 11 lines in total. The only difference to python is that node.js needs normal curly brackets.