I hope you haven't made your decision yet because the comments in this thread are extremely misleading.
First of all, please remember that nothing is faster than a properly written vanilla js application. Every layer of abstraction you add will necessarily slow your app down. You gain convenience at the cost of performance.
So unless you're dealing with major issues in terms of complexity and understandability, I would ask yourself why you need to have a shiny new framework in the first place?
But let's assume you do. You're in the same boat that a lot of companies and developers are in these days - what the hell framework do I choose when a new one seems to pop up every day? Spoiler: there's no right answer. I assume you want your app to be future proof, which is a fools errand, but supposing you're a fool like the rest of us then my humble advice to you would be to read up on web components and choose the framework that embraces them the best.
That would narrow your choices down to Angular 2, Polymer, Aurelia, and probably some other less mainstream frameworks I haven't heard about. Angular 2 would be a fine choice but it's going to be a pretty radical shift to the way people do things, but it will come with a reward of up to 10-15 times the performance of angular 1.+ and react. Oh, and it's not ready yet.
Aurelia takes a lot of its queues from Angular 2 but it's basically production ready today and far simpler in terms of its complexity and API. It's all-in on web components and has a very enthusiastic and helpful community surrounding it.
Polymer is Google's big bet on the future of web development. It's at 1.1 and production ready, and will be extremely well funded for years to come. It's basically sugar for creating web components. It's similar to React in that they encourage you to build your application out of nested components. It's different from React in that it embraces the web components spec and the DOM. React has explicitly stated multiple times that they have no interest in web components.
Polymer isn't quite as simple to get up and running with as React and Google needs to address that, but it's getting better. But the big thing the polymer team has going for them is that they literally share desks with the Chrome dev team, and as such they have their finger on the pulse of cutting edge web browser technology. The React core team doesn't have that luxury, so they've taken the radical approach of trying to abstract away the DOM completely. It's an intriguing approach but in my humble opinion it's hostile to the open web. Make no mistake that Facebook is doing what's best for Facebook. Google is doing what's best for Google, too, but that happens to align with the goals of the open web.
Anyways, I hope you don't just jump onto the React bandwagon before giving your research a little more time. HN is an echo-chamber and the word "React" is just the latest echo you see bouncing around.