Boyd Multerer, who led the development of Xbox Live back when it launched in 2002, and who has been with the company since 1990, is leaving, he announced on Twitter today. Multerer came to Microsoft in 1994 as a contract worker while he worked at his own firm, Zephyr Design, and came to the company full time in 1997. After working on IIS for a time, he became the Development Manager for the "tiny" Xbox team in August of 2000, and led the development of Xbox Live, which made its debut at E3 in 2002, some 6 months after the first Xbox shipped in November of 2001.
Multerer went on to develop XNA, the independent game developers' studio, and then in 2009 worked with Ray Ozzie on an "advanced media project", part of which shipped in TV services for Xbox One and SmartGlass. Interestingly, in his LinkedIn profile, Multerer notes that the rest of the project is "as yet unnanounced". After that, Multerer was the Partner Director for Development for Xbox, where he managed a budget in the "high 10s of millions of dollars", and helped to implement the Xbox One's ability to update in the background, something he'd envisioned back with the first Xbox.
Multerer announced his departure via a tweet and an updated LinkedIn profile, posting that it's "time to do something new".