Linux in general is under constant development, always improving and moving forward with pace.This is great overall for the world of Linux but for its users there is a slight problem.
To benefit from newer packages you typically have to wait until your distribution vendor releases an entirely new distribution that incorporates newer packages.
However what often occurs is the latest release of a distribution includes a KDE desktop that is already outdated and it will remain stuck at this version until the distribution vendor in question releases their next release.
Or a Linux kernel that is several version behind the latest stable release.
If you were to install openSUSE 11.3 this very moment you would get KDE 4.4.4 and Linux kernel 2.6.34
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