It has been only a week since the USB Implementing Forum (USB-IF) revealed details about the new USB 3.2 format and its changes for USB 3.0 and USB 3.1. The USB Promoter Group today released an even faster USB4 standard. USB4 is expected to increase the maximum data transfer rates to 40 Gbps, compared to the 20 Gbps offered by USB 3.2. The new standard is based on the Intel Thunderbolt protocol.
The new interface will use USB Type-C connectors and will retain backward compatibility with USB 2.0, USB 3.2 and Thunderbolt 3 interfaces.
According to a CNET report, the contribution of Intel's Thunderbolt 3 protocol to the USB Promoter Group essentially brings Thunderbolt 3 to PC platforms and allows several companies to integrate their support into their products. Iceberg's upcoming processors Intel will also be the first CPUs to support Thunderbolt 3 inherently, which means that Windows users will not need a Thunderbolt driver plug-in to be able to use it.
However, it is only a draft, which is not official unless it is published later this year (expected in the middle of 2019).
This basically means it will be released shortly before we begin to see USB4 compatibility on devices. Maybe in the 4 quarter of 2019 or early 2020.