Few samples

http://www.photographyblog.com/previews/canon_eos_1d_x_photos/

Dan Chung has a very informative Video on the 1DX on his site:

http://www.dslrnewsshooter.com/

Mitch of Planet 5D made this list of points of interest from the video:

* No line skipping in video – uses whole sensor (4:50)
* Very little rolling shutter (5:00)
* No clean output but there’s no blackout and no frame rate drop either (6:10)
* Still a division between HDSLRs and the video cameras with HDMI out (6:25)
* Some samples of the new menus and audio controls (7:05)
* Display of audio levels and using silent controls (7:25)
* Can use shutter button to start/stop movie recording (and use remote controls) (9:00)
* Time code options (9:40)
* New dedicated button for magnifying image (10:45)

@Mihuel
"Because the manufacturers know the Achilles heel of customers. Everyone wants to have a longer dick than his neighbor. The numbers, even if they do not understand, act on the human psyche."

This is so true. I remember having an argument with a guy at a party once and he didn't believe me that 720p is better than 1080i. He couldn't comprehend the fact that with 1080i he is actually watching 540 lines at a time where as in 720p you are getting the full 720 lines at a time. He was sold on the fact that 1080 is a bigger number than 720 is so it must be better. I had to walk away from the conversation laughing.

@Mihuel: The GH2 is my first foray into digital video. I made an independent feature film in the 1990s and it was 16mm film all the way. This is much more convenient, time and cost-efficient, and overall better image quality even given film's better latitude and color space IMO :)

Vincent

Most major movies are still post-produced at 2K resolution. 4K is great for huge cinemas, but complete overkill at home IMO.

Vincent

In the economy we are going I don't expect 4k very soon. A 60 inch 1080p inch screen will be plenty for most for a long long time. It is not just a question of the bigger is better but the constraint of room size etc that will play.

That's right, but the SMPTE tests from the nineties are considered widely as precise in the scientific community.

You said "Brain and human vision work in quite complicated ways."
Totally correct, my neighboring department of Media Sciences is leading some important work in that field. They can already tell that contrast and the integral under the MTF curve is more important for the impression of resolution than limiting MTF as given by manufacturers (read up on Otto Schade's groundbreaking research from last century, seems he was right).

To me, 720p (as German/French TV is broadcasting) looks about as great as Blu-ray on my 1080p projector as on a friends 720p one from normal viewing distance. It shows so much more clarity over upscaled DVD that it seems like 35mm vs. 16 in last centuries cinema. Even in todays cinema only the first few rows could see the difference between 4K and 2K, the human vision doesn't resolve it from farther away.

BUT there's a big difference between necessity of 4K for viewing and 4K for production! Having 4K at the source will improve quality even when downscaled, will end moiré issues, will allow better VFX work, re-framing or stabilization. I'd take a 4K camera for a decent price any time, but I won't exchange my projector before it dies.

4k content down-sampled to 1080p will still look better than stock 1080p. A bit like how HD down-sampled and broadcast at SD looks better.

Affordable 4k would be awesome for content makers.

But guys, where you gonna get 4k content? Most movie theaters don't even have 4k. You want some fantabulous projector to look at your own projects? I like my work too, but I don't like it THAT much.