As I said here the last time a new React version came out, we're using React for more or less all new JS development at Khan Academy, and we're loving it.
In short, it's simple (very little to learn) and very fast. One other big thing I love is that it encourages building reusable and composable components. Angular has a lot of the same structure, but if you end up building directives then you have to drop down to manual DOM manipulation again if you want speed.