Call of Duty: Modern Warfare Remastered is launching alongside Infinite Warfare later this year, and judging by the video embedded below, the graphical enhancements are quite impressive. The footage shows a playthrough of the Crew Expendable mission, the second chapter in the original 2007 game.
The lighting is the most striking improvement: the darkness is less grey and more authentic, while the ship's floodlights cut through it more convincingly. Elsewhere, the character models are more ornate, and the textures don't look as low-detail and drab as they did in 2007 (of course, it looked much more impressive back then).
Modern Warfare Remastered releases alongside Infinite Warfare on November 4. For a while at least, you'll need to buy Infinite Warfare to get access to it. Details on all that are over here.
Here's the new footage:
...and to compare and contrast, here's footage of the original playthrough, courtesy of YouTuber Ross Mahon.