The problem is we don't know what the boffins in their white coats have been cooking up in the labs.
If you watch the video the rep mentions a few times that the 1DX is a PRO Photography DSLR camera, the video was extra.
He makes that point clear a few times.
This is why it sounds to me like they are going to try and release a PRO Video DSLR e.g. the next 5D model being that its been accepted unofficially by the industry as being the video DSLR of choice already.
You mention line skipping but as they said in the video that it has been reduced dramatically with the new sensor, remember that this is the Photo DSLR, it then makes me wonder what the Video version could achieve.
I think the line skipping has been reduced(certainly in the 1Dx) because of better/more processors. They cant give a 5D this type of fire power in 4k or it will be essentially capable of faster fps of stills as the 1dX
You have a good point about the brand name of 5D for the video industry. Maybe we see a 5Dmkii-s that is video dedicated. However, I don't think that's in the lineup for nov 2. I think Canon needs to hit the Red scarlet from above and below in terms of pricing/features, and I think they will.