You may have also heard that the next Ubuntu version--Natty Narwhal, version 11.04--will use the 3D-enabled Unity desktop by default instead, along with the Wayland graphics system.
Unity is still based on GNOME, so it won't affect the use of any GNOME-based applications, Canonical says. It will also still be possible to reinstall GNOME, if you really want it.
Nevertheless, desktop environments can vary tremendously, and those differences can have a big effect not just on the appearance but also on the speed of your Ubuntu installation. Now that there are already big changes coming down the pike, this is a particularly good time to take a fresh look at the Ubuntu desktop and all the many free alternatives that are available.
Here are a few particularly worth considering.
KDE is no doubt the best-known alternative to the GNOME desktop, and it's what you're already used to if you run Kubuntu instead of the standard desktop Ubuntu.
KDE and GNOME both offer much the same functionality, differing instead on the way things are presented on the desktop. GNOME's desktop has a reputation for being simpler, while KDE's tends to offer numerous options, causing some people to find it more complicated.
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