AngularJS 2.0 team member Rob Eisenberg recently explained the relationship between AngularJS and Polymer:
“Angular is really designed around optimizing application development (including DI, routing, templating and decorator directives, more advanced databinding)”
“while Polymer is really optimized around custom element development. So, it has basic templating and binding and a strong component model.”
Therefore, Eisenberg expects people to implement cross-framework UI components either as pure Web Components or via Polymer. He thinks apps and app-specific components are more likely to be built in Angular.