The Angular team is currently exploring options to ease the upgrade path - the current plan last I saw is to create an engine that runs angular 2 components in

The Angular team is currently exploring options to ease the upgrade path - the current plan last I saw is to create an engine that runs angular 2 components in angular 1 and vice versa for seamless interop, so upgrading can be more incremental. That is an evolving story, which has changed several times before reaching that point. That said, Angular 2's performance is already looking phenomenal, and assuming some of the stats I have seen out in the wild are to be believed, it can run over 30x as fast as some of the existing frameworks for large datasets, including angular 1. If I had to choose a library to use now, it'd be React, but if I had the opportunity to hold off upgrading, I would absolutely wait for Angular 2.