[cookiecaper]

I'll assume you meant of course KDE4 is like KDE3, but that's not what they were going for way back when they first announced the project and wanted everyone's ideas for how to innovate the desktop. They didn't really come up with anything.

Plasma might have been inspired by Dashboard, but it may not have been, and it definitely allows things that Dashboard doesn't.

Expose is part of almost all compositing window manager plugin sets of which I am aware. I don't know if OS X was the first to do this, but I don't think it's all too much of a stretch to suppose that it might be useful to see all the windows all at once occasionally.

Spaces is a non-starter; Linux DEs have had them for dozens of years, OS X 10.5 was the first appearance in OS X.

I agree that the preference panel is similar.

KDE 4 also has a huge taskbar and what is essentially a start menu. It uses a very conventional, Windows-like approach, and although it may have cribbed a few features from OS X too, Windows 95 is the dominant paradigm for a default KDE 4 installation.