In the MSDN documentation it says:
Azure supports Notification Hubs as part of the Azure SDK 2.1, in the Microsoft.ServiceBus.dll assembly. You can now create, update and delete notification hubs programmatically, manage your device registrations, and send push notifications to all your mobile clients across all platforms (Windows Store, Windows Phone 8, iOS, and Android).
I cannot find any documentation on creating and managing the hubs programmatically or any code samples, we are currently referencing v2.4 of the Microsoft.Servicebus.dll.