I'm going to get flamed for this, but I deeply regret the hours I put into learning Angular.
I'm still disappointed that Angular 2 is such a sharp departure from Angular 1 and certain aspects of Angular 2 development, e.g. the fact there is still multiple CLIs, the fact that "compiling to Dart" is still a thing, and the fact that it's still unreleased give me no confidence to build anything in Angular. I can't help but feel that with any library, less is more, and that Angular 2 is already trying to do way too much. IMO Angular 2 should be a Typescript-only library with one CLI and one way to manage your files (among other changes made in the name of simplicity).
All this being said, I hope I'm terribly terribly wrong, and Angular 2 becomes the super-simple-way-to-create-great-UIs that the authors intended that the whole community can follow along. This article however, made me ask myself if that will ever happen.