More than a year on, and we've got 120fps on a GoPro, but just scaled up 1080p60 on the 1DC. I figure that by this point if it was going to happen, it either already would have, or Canon would have said, "We've got an exciting announcement. We're going to bring out a new feature in three months time," as they did with the C200 or HDMI out on the Mk3.
By the way, I think the 1DC is still a worthy camera, especially now that used 1DCs are starting to show up for AU$6000, AU$7000. But it's a niche thing -- for people who really hate external boxes, or really love Canon colours, or need high-quality stills and 4K in the one body, or think that the look the camera provides suits their project (8-bit and "only" 12 stops of DR can be an advantage -- just depends on what look you want).
Just wanted to add a +1 to Matt's comment. My work is mainly weddings. I was already considering a C100, but the lack of slow mo was the main turn off, so I do find the update significant. There's particular moments in weddings, like throwing rice outside the church door, when slow motion really adds a lot.
What I like about the C100... Well, wedding guys have different priorities from people doing controlled shoots. Low-light ability, being able to record hours and hours of footage to SD cards, continuous recording over 30 minutes, dual pixel AF, long-lasting battery, great look out of the camera, and the ability to record a backup, in case of card failure, without attaching an external recorder -- these are all huge plusses -- butt-saving, shoot-saving, thank-God-for-this-feature plusses -- though these are also all things that don't matter too much to someone who's mainly doing narrative.
Add to that that I'm already heavily invested in Canon, and that, for weddings, you need 3-5 cameras, not one camera -- so you need something that's going to kind of match your existing cameras, without grading, if you don't have the money to upgrade all your camera bodies at the same time.
Anyway, so I think considering a C100 Mk II is quite rational for me, though of course I appreciate it's horses for courses -- that everyone's needs will vary...
Yep. There's a write-up of Girl With A Dragon Tattoo in American Cinematographer. Jeff Cronenweth says, “David also likes to have the option of manipulating the final composition or stabilizing the image, and with the Epic we had 5K to work with. We utilized the extra resolution to create our own frame lines, smaller than what you get using the entire sensor. Actually, we did that with both the One and the Epic, allowing room for repositioning shots. For example, if an operator clipped an eyebrow on a tilt up, we had plenty of space to correct the composition. We also used the extra space created by the extra resolution to help stabilize many shots, including all the driving footage we shot in Stockholm.”