System76 released the first stable version of its Rust based COSMIC desktop with Pop!_OS 24.04 LTS. The update adds rewritten core apps, new tiling and workspace controls, and the new COSMIC Store. Available now for download or preinstalled on System76 devices
I find it pretty solid if a bit bare bones. With the basics in place, it should improve fairly quickly.
They are planning a 26.04 LTS release. We will see what it looks like by then.