With no Sony to compete with for attention at its E3 2019 press conference, Microsoft could have easily walked into its annual Xbox event, thrown a few games out, and called it a day with few people disappointed.
Instead, the company stepped in with a flurry of game trailers (admittedly light on gameplay or 2019 releases), news about Project xCloud, and most interesting of all, details on its next-gen console codenamed Project Scarlett. It was a busy, rapid-fire hour and a half stuffed with world premieres and new announcements, and Xbox Game Pass availability of some kind touted for everything shown.

The crowning moment of Xbox's E3 2019 press event was its announcement of details surrounding its elusive Project Scarlett, which is incidentally what it's still referring to its next-gen console as for the time being.
It did confirm that the console is in the works for a release of Holiday 2020, where it will launch alongside Halo Infinite. The console is allegedly four times more powerful than the Xbox One X, and is made by the same team that worked on last year "most powerful console."
Broken down, Microsoft claims that means framerates up to 120fps, 8K, next-gen ray tracing, variable refresh rate support, and an SSD being used as "virtual RAM." For the processor, Microsoft has partnered with AMD to co-engineer a brand new piece of technology. And as Phil Spencer put it onstage, Project Scarlett will be a console that is "100% focused on games.
Though that's all we know at the moment about Project Scarlett, it does seem likely that it ends up having some kind of close relationship with Microsoft's endeavors into cloud gaming, which it also offered more details on during the presentation.