We're told that the upcoming Canon EOS-1D X Mark II (if that's the name) will indeed shoot 4K video, which sounds like good news. However, we're told not to expect a very video orientated product, as the camera's primary focus will be on the still photographer. We're also told that this will be the only next generation DSLR in the lineup that will shoot 4K video at launch.
There will likely be another EF mount product some time in the next 18 months that will shoot 4K, but it won't be a DSLR.
Not much else is being said about the next iteration of Canon's flagship DSLR.