The FAA has mandated that all hobby drones have to be registered. The website opens on Dec. 21 but you may be confused whether or not you have to register. Well WIRED cooked up a nice little reference chart: http://www.wired.com/2015/12/drone-register-list-faa/
Check it out. Long story short: If it says 'DJI' like most general hobbyist's rigs do, then you better plan to register. It's all online and it costs $5. Which is a lot better than the up to $270,000 fines you could incur!