According to Japanese website DigitalCamera.jp, the upcoming Nikon D4S DSLR will have same memory card slots as Nikon D4, which is one CF card slot and one XQD card slot. The design of Nikon D4S has no change from D4.
Here is comparison of the memory card door.
The Nikon D4S now already listed on B&H Photo Video website, not available for pre-order yet, and specs is not available yet.
via: NikonRumors