Ubuntu13.10 uses Mir by default. Kubuntu indicates not to follow

Canonical announced that Ubuntu13.10 will use the Mir Display Server by default, while Canonical originally planned to use Ubuntu14.04 by default, which is optional in 13.10. Canonical accelerates the popularization of Mir in order to have more time to test, because Ubuntu14.04 is a long-term supported version. In Ubuntu13.10, Mir runs the Unity7 desktop using the XMirX11 compatibility layer. If the graphic driver does not support Mir, it will support running X. Org.

Canonical announced that Ubuntu 13.10 will use the Mir Display Server by default, while Canonical originally planned to be used by Ubuntu 14.04 by default, which is optional in 13.10. Canonical accelerates the popularization of Mir in order to have more time to test, Because Ubuntu 14.04 is a long-term supported version. In Ubuntu 13.10, Mir runs the Unity 7 desktop using the XMir X11 compatibility layer. If the graphic driver does not support Mir, it will support running X. Org Server. Kubuntu, a community release based on Ubuntu, indicates that it will not switch to Mir after Ubuntu and will still use X. It is planned to switch to Wayland in the future.

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