About a year ago, I was beginning a new (personal) project, and thought maybe I'd learn Angular... went through a few online tutorials, seemed fairly pleasant to work with. Then I ran across the news regarding Angular 2.0, that it would be more or less a completely new framework. Not sure if that's true or not, but there was enough confusion in the blogosphere around that time that I decided not to sink the time into learning a new framework whose creators had already declared obsolescent.
Backbone is the old reliable, I'll stick with it for the time being.
P.S. I don't consider myself a frontend/js developer -- I only ever do front-end work on my own personal projects, because there's nobody else to do it :)