The GNOME desktop's Mutter Wayland version has been released ahead of the official GNOME 3.10 release later in September.
Mutter is the window manager to the GNOME 3.x Shell and the Mutter Wayland version is of the Wayland code branch
for compatibility with this X11 alternative. Mutter 3.9.91
was released earlier this week while out today is the Wayland 3.9.91 version
Over the X11 Mutter, the Wayland version has support for the DBus API for display configuration, an X IO error handler for XWayland, Clutter xkbcommon integration for the Wayland keyboard, plugin modality for running as a Wayland compositor, support for the application menu for Wayland clients, and various other Wayland-specific changes.
As I happened to talk about earlier today, GNOME 3.10 should be in good shape for running on Wayland
when released before month's end.