We are informed Canon is planning to introduce a new camera in the second half of 2014, possibly called the EOS-3D. It appears to be the big brother of the current EOS-5D Mk III and may come with a much higher resolution sensor and 4K video option features.
The price will be 'much' higher than the EOS-5D Mk III and if true, the replacement Mk IV camera will be pushed into 2015. Ever since the retirement of the EOS-1Ds Mk III and EOS-1D Mk IV, Canon is left without a professional 'mega pixel' and 'sports' camera respectively. Although the current EOS-1D X can shoot at lighting speed of 14 fps, it is technically not classified as a sports or wildlife camera.
I would welcome a new sports camera designated as the EOS-1D Mk V but it may come with a new DSLR body design. My only 'complaint' with the EOS-1D X is the full frame sensor sometimes lacks the additional reach of the APS-H. I loathe carrying heavy Super Telephoto lenses around on my photo shoots and use extenders only sparingly. The only exception I make is for the EF 200-400mm f/4L IS USM Extender 1.4x lens. Keep checking back for the latest information.