Hello IoT Community!
You can now use Node.js on Windows 10 IoT Core to communicate with Azure IoT Hub.
The IoT team published a tutorial (found here) that will take you through steps to get started with Azure IoT hub.
In this tutorial, you will send data to your IoT hub from a light sensor connected to an Arduino using a Node.js app running on a Raspberry Pi 2. The app you create will make use of Johnny-Five to communicate with the light sensor and azure-iot-device-mqtt to send the data to the hub.