During his presentation at E3 2018, Phil Spencer of Microsoft confirmed that they are currently working on the next generation of Xbox consoles. He said that the company was "deep into architecting the next Xbox consoles where we will once again deliver on our commitment to set the benchmark for console gaming."
Image credit: Microsoft
Following on from this, Brad Sams of Thurrott, has received a tip off about the consoles under development - namely that the code name for the project is 'Scarlett' and the expected launch date is some time in 2020.
Obviously a lot can change in two years, but from the information Sams was able to verify it would appear that Microsoft is currently on track for a 2020 launch.