I think Node is going to become a big player in server-side code, and we may even be so lucky as to have it usher out PHP as top dog. JavaScript is a great language, and being able to run it both client and server-side and have them be able to "talk" to one another, coupled with task runners like Grunt and Gulp is huge. Front-end libraries come and go, and I expect the current crop to do the same. Front-end libraries have a problem with overhead, and until we can get a handle on that, perhaps by pushing some of that to the server, their days will be numbered.