This is the third alpha release of CircuitPython 6.0.0. It is relatively stable. The release is still alpha because some API changes and additions are not yet included. Upcoming in a future release but not yet included are ESP32-S2 Wifi support, and _bleio HCI support for ESP32 co-processors.
The most notable additions since 5.3.x are basic lower power support when in time.sleep() and initial ESP32-S2 support. The lower power work changed time keeping and may have introduced bugs. Please use 5.3.x if you need a stable version of CircuitPython.
Downloads are available from circuitpython.org. The site makes it easy to select the correct file and language for your board. The downloads page is here. Downloads are no longer available from the GitHub release pages because of the large number of files for each release.
To install follow the instructions in our new Welcome to CircuitPython! guide. To install the latest libraries, see this page in that guide.