It always baffle me how little people here talk about DurandalJS (that uses knockout for its bindings). It is a nice alternative to angular... and it uses knockout which is awesome. If you like knockout, you should really take a look at it.
An example, we have an app that so far consists of about 25 individual SPAs. It was originally an SPA, but we ran into tons of problems with routing issues that cropped up, and realization that when the user uses the apps, in any given session they'd probably only use 20% of what it offers. Developers get to work quickly on their modules, there's no up front initialization/download of the entire apps. Some of the apps are more prototype quality to get the job done, some have been refactored several times. But they all form a cohesive experience. It's also nice when you're developing a group of functionality that you don't have to start the app at the beginning.
Most users won't even know when their in a SPA vs Multi-page SPA.