What does the adoption of the DCI-P3 colorspace in the new iMacs mean for us? Is this a default or simply an optional setting? Does video produced in other standards like sRGB or Rec 709 get displayed correctly when set to P3? Is this setting something limited to only these displays or will software updates or other displays like Retina MBP enable this feature, too?
It should be like any other wide gamut screen out there. sRGB content should look like sRGB and P3-content should look like P3. I do hope Apple has the option to force OS-wide sRGB in the hardware as some apps don't use color profiles - including VLC. If there isn't an option for that these screens could be a huge problem.