Earlier this week ExtremeTech took a closer look at the new KDE4 Linux desktop:
Linux users are as evangelical about desktop environments, the all-encompassing graphical user interface software responsible for providing everything from taskbars to office suites, as they are about operating systems. It shouldn't come as any surprise, then, that the first major release in over five years of the most popular desktop environment available is causing quite a stir. Due to be released on December 11th, KDE 4.0 is bringing exhilarating graphical, usability, and functionality improvements to the Unix-like systems it is designed for—and Windows users will get a taste, too..
You can read on over here. The reporter says KDE4 looks very promising and might make it into mainstream in a couple of months as the new version won't only be for Linux but also for Mac OS X and Windows.