Steven Sanderson recently published his talk "Architecting large Single Page Applications with Knockout.js". It shows new features of KnockoutJS 3.2, especially components.
Components are reusable parts of application that have their own view model (or rather a factory function) and template HTML. They are inspired by web components. A KO component is first registered and then used as a custom HTML element. KO implementation of components works down to IE6. Examples can be found from here.
The talk also included points about using yeoman scaffolding (probably easiest way to get started with large applications with KO), build systems (grunt, gulp) and TypeScript.
More information on the new KO version: