There's one very often requested feature for keyboard layout switcher - 
to be able to use modifier-only shortcut for switching layouts. E.g. 
Alt+Shift or Ctrl+Shift like it is on Windows. As far as I know kde3 
KGlobalAction did not allow that. Is there any possibility this may 
change for kde4? If not I could try to make this available only for kxkb 
by intercepting X events in kxb (possibly via libxklavier) as this may 
be needed only for kxkb?

Thanks,
Andriy