We're using more React Native every day at Facebook, including several parts of our main apps and the Ads Manager app which is completely built in React Native (and shares 90% of its code between iOS and Android). It's probably still a few years before we might do all new product development in React Native – but it's not going anywhere. Around 100 engineers at Facebook are building products in React Native.
I'm not sure what improved tooling you're looking for in particular, but the Nuclide (https://nuclide.io/) team at Facebook is always building out new features to help React Native devs. I would be remiss to not also mention VSCode and its excellent React Native support (https://github.com/Microsoft/vscode-react-native). You can watch demos of both projects from React.js Conf earlier this year: