Game Pass is a subscription-based service that lets you stream over 100 games to your Xbox for a monthly price of $10, £8 or AU$11. It's a lot like Netflix for video games, with access to a changing library and the ability to play highly anticipated games on launch day.
Microsoft has slowly been making Xbox more integrated with Windows, and support for Game Pass on PC is yet another example.
Although Nadella mentioned that Game Pass would be coming to PC, he didn't provide specifics about when that would happen. There's also no word yet whether the PC Game Pass would share the same library of games as the one on Xbox.
Microsoft didn't immediately respond to a request for comment.