Ubisoft has stated that Gunsmith CAN be used without Kinect. So its all good guys.
This is a Q&A from their forums.
"Can you use Kinect apart from Gunsmith? (Cesar A. Gonzalez)
Answer: Kinect will improve Gunsmith experience to both create your very own weapon and to test it in a close-to-magic experience: more information here. However, the game itself is designed to be played with a controller and thus Kinect won’t be used outside of Gunsmith. Please note also that Gunsmith will still work without Kinect."
