I’ll focus on Ajax orientated JSON structured projects. Most people already know how easy and straightforward the data-binding with Angular is.
The benefits in Developing Single Page Applications (SPA) with Angular are several and considerable. There are many advantages by using Angular, for instance being able to improve your Test-Driven Development or the Behavior-Driven Development. By declaring your UI and placing markup directly in the HTML, the presentation is kept logic in one place and separated from the imperative logic. The key is that the shaping is done right there in the markup rather than in some isolated code.
Furthermore the dependencies injection is handled very well, both for testing and for SPA development.
Some people migth say that for huge applications the SPA is not a good strategy, but in such case the best approach would be the hybrid SPA, that consists in dividing the application in as many SPAs as web sections. The force of this strategy is the development divided in directives consisting in new HTML elements and attributes.
Such structure permits an optimized workflow between design and development, which allows a high grade of parallel development. The aim should be to break down the actions into their own services and sub controllers, so that developers could independently test the code without crashing into each other.