Modern Warfare 3 will have a 'Colour Blind Assist' option, Sledgehammer has confirmed.
VP of the new COD studio Michael Condrey confirmed the feature in an answer to a reader question on the Sledgehammer blog - but not before laying down some stats:
"Research suggests that as much as 6% of the general population suffers from Color Blindness, or more accurately Color Vision Deficiency. Men (9-12%) are 20x more likely to be afflicted than women (0.25-1%).
"Those numbers vary depending on which source you quote, but we estimate that nearly a million gamers are playing Call of Duty every day with this issue. I am happy to report that we are working on a Color Blind Assist option for Modern Warfare 3."
Condrey pointed out that blaming poor multiplayer performance on a bit of colour confusion would no longer be an option. We suggest using the brand new killstreak system as an excuse instead.