GNOME 4 and GNOME OS is being targetted to be released on March 2014, which is less than two years from now according to the developers in GUADEC conference. They also expect to have 20% market share by 2014. Looks too ambitious for me, because they failed to impress most of their users with GNOME 3 up to today.
We can see the most visible fact is that Ubuntu is no longer the most favorite Linux distribution out there. Nowadays, people prefer to use LinuxMint, it's derivative maintained by Clem who happened to be the maintainer of Cinnamon as well. LinuxMint succeed to take over the angry and unsatisfied by Canonical's decision to revamp Ubuntu's UI.
Meanwhile, KDE is looking a stable new release in the next few days and it's growing strong each day. Even with some uncertainty of Qt development sometime in the past, they have managed to struggle and keep going on with the roadmap ahead. They are now preparing the next major release of Qt which should be released by next year. KDE 5 will soon be based on Qt 5. Looking forward to see KDE 5.