I assume you read it too, as well as the comments? There is a benefit to pushing (Mir/Wayland) out to users, even if they are using X(Mir/Wayland) to actually run their programs, and even if Xmir is not very different at this point from Xorg. Apart from wider testing of Mir itself, several other points are brought up in the comments.
Posted Oct 2, 2013 17:46 UTC (Wed) by tuna (guest, #44480)
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The only point I found in the comment was that it would be technically possible to have better VT switching, but that is not enabled in the current Mir/XMir setup.