KDE Plasma Workspaces is frozen as development efforts are focused around the next-generation version to use Qt5 with KDE Frameworks 5, which is now entering a usable state, will be in a preview form in December, and should be in great shape for 2014.
While Plasma Workspaces is frozen, the platform and applications code continues to receive new work for KDE 4.12 to serve as a stable interim release around the middle of December. With this first beta of the KDE 4.12 changes, the code is now under an API, dependency, and feature freeze. Among the changes to find with KDE 4.12 are a GPG back-end to KWalletD, Python and Scilab back-ends for Cantor, matrix support in KAlgebra, many KDE PIM improvements, KNetWalk has been ported to QML, and numerous other platform changes. KDE 4.12 is mild on new features.
More details on today's KDE 4.12 Beta can be found via dot.KDE.org.