Behold, Call Of Duty: Modern Warfare Lets You Reload While Aiming Down Sights.
"One other thing we added this year is the ADS [Aiming Down Sight] reload. In the past, if you're ADS, and you're shooting and you reload, the weapon would go off to the side, and you'd have to retrain to get to your target," Grigsby said in an interview for Activision. "This time if you reload, it stays on the target, so you can stay in the battle."
Also in the interview, Grigbsy spoke at a high level about why the reload animation is so important for Modern Warfare. "The reload to me is the pinnacle of the weapon; it makes you feel--after you've taken down five different dudes in a room--and you reload, you go, 'Sh*t yeah, you're done!'" Grigsby said.