Polymer is a framework based on web-components (a relatively low level fmk - it's not angular). Webcomps is a coming standard to be implemented natively by browser, so you'll have a native components model, at last ! But webcomps aren't ready yet. Polymer is heavily based on polyfills and is slow or won't work on older browsers because of that. But yes, Polymer has a great API.

I'd say React is the best response TODAY if you want a component approach.

And if you want to see what future could look like, give a try to Polymer Dart =)