Kiosk Tool is ancient, unmaintained, and generally only works with KDE3, which none of our recommended distributions ship anyway.
IMHO we should remove references to Sabayon too.
As part of this bug, we should add a note that TLDC will not add applications to the desktop in KDE4, since these are Plasma widgets by default and not desktop files. You can change this manually by setting the desktop layout to "Folder view".
I'm not fully convinced of the merits of this change. Although I agree with that Kiosktool is not usable nowadays, I think Sabayon is a nice tool. We are also using it on our demo system, so it is certainly useful with ThinLinc.
But of course, users can use Sabayon even if it's not mentioned in the TAG. The newly added text about KDE4 is also good. So, test passed.