Comparing PHP and Rails to Node.js is not quite right, as PHP and Rails are application frameworks and Node.js is primarily a platform for creating application servers. There are a number of more analogous frameworks being written on top of Node.js, but none of them have reached a similar level of maturity and adoption yet.

I believe that the author is arguing that Node.js could reach a similar level of popularity as Rails if there were a framework that provided some of the ease of use for common use cases, such as creating typical CRUD apps. However, he also states that in order to displace Rails, such a framework would also need to offer some distinct advantages, such as better support for realtime.

Backbone, Ember, Knockout, etc. are client-side frameworks. They make it easier to structure complex client code, but they don't include a simple solution for creating a server or synching data among clients and servers.

It's still under active development, but I have been working on a full-stack framework on top of Node.js that is more like what the author was envisioning: http://derbyjs.com

Derby provides server and client rendering, and it automatically synchronizes data in realtime. The idea is to make writing realtime apps so simple that any app can take advantage of advanced realtime features, fast server-rendered page loads, and instant client-rendered page updates.