Corrine Yu, the now former Principal Engine Architect at Microsoft's 343 Industries, has left the company to become a Graphics Programmer at Naughty Dog. Yu, who had worked for Microsoft for more than 5 years and had become one of 343 Industries' most recognised developers, therefore brings a wealth of experience and added publicity to the Naughty Dog team.
It seems she's already hard at work on one of Naughty Dog's PlayStation 4 projects (presumably Uncharted 4) and enjoying the career move, if her now-deleted Tweet ("I am loving PS4 graphics coding. No more Windows 8 for me. So happy!") is anything to go by.