Version: (using KDE KDE 3.4.92) Installed from: Compiled From Sources It took me a while to track down the culprit for this.. as I originally thought it was the pager/desktop previewer.. When using the "For Transparency" appearance type for the taskbar, switching between desktops takes about 5 times as long, especially in comparison with the other appearance types Elegant or Classic, which are near instantaneous. It seems that the 'effect' used to outline the text is not cached and has to be 'recalculated' each time a change occurs with the button (such as changing desktops). I currently have alot of windows open (16) so this may also be correlated with the number of taskbar buttons and the number of times the outlining of text has to occur, thus it gets slow as you have more windows open. Another ill effect of this is a 'ghosting' type effect if you drag your mouse over all your taskbar items quickly.
*** This bug has been marked as a duplicate of 108603 ***