The story of KDE's user revolt is well-known. What is less well known is that, in the six years since then, KDE has been steadily regaining its user-share.
In fact, for the last few years, KDE has registered as the most popular desktop among experienced users. Despite the obvious limitations of reader polls, they show KDE's popularity consistently well ahead of Xfce, the usual runner up, in2011, 2012, and 2013 in LinuxQuestions' Members Choice Awards and in Linux Journal's 2013 Readers' Choice Awards. Even assuming a wide margin of error in the polls, the consistency makes KDE's recovery hard to question.
Read the full thing at http://www.datamation.com/open-source/nine-lessons-other-desktops-can-learn-from-kde-1.html