Short bio: Computer Scientist, FOSS supporter (read more)
Tux Machines (TM)-specific
KDE 4 is a radical overhaul of the popular desktop. It offers broad improvements like the Oxygen desktop theme, SVG graphics, and enhanced speeds thanks to the latest version of the Qt 4 toolkit. It also offers specific improvements such as the font manager and the Dolphin file manager. In short, there's a lot to like.
But, as might be expected, not all the changes are equally successful. Nor is the situation helped by the fact that KDE 4 was a preliminary release, and the project intends the upcoming 4.1 as the production-ready version -- as you might expect, most distros have rushed to include the early minor releases as soon as possible.
After a week of regularly using KDE 4.0.2 and 4.03 releases on my laptops, these are the improvements that would enhance KDE the most:
A more customizable panel
In the rush to get KDE 4 out the door on time, the first version came with an unresizable panel stuck firmly at the bottom of the screen.