The desktop environment update is currently pencilled in for release on March 26, but GNOME’s Matthias Clasen is now keen to move the date back to “align the [GNOME] schedule with the Wayland release plans“.
GNOME 3.12 is the first version of the desktop environment to fully support Wayland (a XServer replacement that combines the role of display server and compositor).
The entire GNOME desktop stack has been ported to the protocol, with the April 1 release of Wayland 1.5 including a number of core components required to achieve it.
No Decision Yet
A decision on whether to hold back the release by a week or not has yet been taken. But it seems like a fair trade off for super stable Wayland support.
In the interim the two beta milestones for 3.12 remains on course for release in mid-February and early March respectively.