A new job listing on Sledgehammer Studio official website confirmed that they are working on next Call of Duty game. The studio is looking for a Senior FX Artist to help "create the most exceptional real-time effects with hyper realism for [its] next Call of Duty game".
The job listing states that the candidate must have a solid professional experience and knowledge of the limitations and performance of current generation hardware (360, PS3).
This means that next Call of Duty game may also come out for current generation consoles. You can check out the job listing HERE.