I write a lot of hobby/side projects just for experimenting and learning, and Angular has become my framework of choice. You can just get stuff done so quickly and easily, particularly after you've been using it for a while.
Angular has a sort of jagged learning curve. It's shallow for quite a while, and you can do a lot of work in that shallow half. However once you need to start writing your own directives, the curve steepens. It's not the steepest curve, but there's definitely a transition. This is when you hear people talking about Angular being difficult, citing things like transclusion.
I've made it to the other side of the curve, and I love writing directives and services, it's become fairly intuitive to me. With the modular architecture, if you there is a large library of available modules/plugins, even people who don't want to write a lot of JS and understand Angular to it's core can do some amazing things. That's why I built http://ngmodules.org , so that people can share modules, and AngularJS can be accessible to more people.