I started using KDE 4.0 from about a week after it was released as i was fed up of kde 3 (vanilla,not kdemod) and those days KDE was full of bugs,including file conflicts ,library problems and many more.but after sometime (about 4 months) KDE was better and my opinion is now it can be used for daily work!
These are snapshots of my desktop ,
When switching from desktop (1st one ,it’s a rotating cube) to other using compiz-fusion! (Zoom)
Some other effects. (Zoom)
Best Alt+Tab window switcher! (clearer than others) (Zoom)
When a window is clicked and hold (the window bar) the transparency increase (Zoom)