Angular is a popular framework for creating front end web applications. These run in the browser and provide great experiences for headless CMS scenarios and custom web applications alike. Together with server side rendering coming in Angular 2, it is perfect for building fluent content experiences on Drupal 8 REST APIs.
At the Angularconf 2016 Matt Davis from Mediacurrent discussed the collaboration between the Angular 2 and Drupal communities. Currently Drupal is missing a comprehensive front end framework and is looking at coupling together with Angular to provide a more contemporary administration editing interface.
Drupal and Angular communities are forging a relationship that might have a significant impact on the future of both systems. It seems like a good match to couple Drupal 8 with Angular 2 as both have gone through large changes in the future, but Drupal 8 still lacks a coherent de-facto SPA framework.
Decoupling Drupal and working with a front end framework has been a hot topic in the Drupal Community for a while now. Dries Buytaert has discussed the prospects of different options, and has even credited the Angular 2 team for changing their licensing to be compatible with Drupal.