The Steam Controller is odd. Even after a bit of hands-on time, we were a bit confused. Clearly, Valve's unique approach to game input will require a bit of a learning curve. And, it may need some more user feedback to iron out the kinks. That's why the company is planning on shipping out another batch of Steam Controllers to developers and users.
Speaking to Kotaku, a Valve representative confirmed that they will be making more controllers to send to the public and that they are "planning on continuing to make and distribute controllers to both developers and testers." There are no specific dates at the moment, however.