The main feature to X.Org Server 1.14 is pointer barriers and barrier releases, which were just merged to master. Since September there have been a variety of fixes including work on XWin, MinGW fixes, DIX work, and nearly two-hundred other commits.
Unfortunately, XWayland was not merged for X.Org Server 1.14 nor any other really interesting features.
The final release of X.Org Server 1.14 is expected in March.
The X.Org Server 1.14 RC1 release announcement with change-log can be found on the xorg-announce list.