This release candidate is also coming on time with the merge window having just closed (it actually closed two days late, but that was due to his holiday). The 1.11 release schedule puts the final copy going out in mid-August (19 August), which is just a few weeks before the X.Org conference in Chicago that I am organizing.
Since the release of X.Org Server 1.10 earlier in the year, the 1.11 RC1 adds 30,588 lines of new code while dropping some 35,662 lines of code. Overall though, the 1.11 release isn't particularly exciting. It doesn't have X Input 2.1 with all of its touch features as that's not coming until X.Org Server 1.12 now. On the input side though, support for pointer barriers was added. Peter Hutterer has also proposed merging some of the input work and releasing that as X Input 2.1 to go into this release, but as of RC1 it's not been merged. Xres 1.2 patches might also be merged if they can get cleaned up by the xorg-server 1.11 RC2 release.
RandR 1.4 also hasn't returned. There is though a whole heap of XQuartz changes from Apple.
Also to be found is a lot of bug-fixes and other work, as talked about in the release announcement.