I work as an audio/video technician at my college. A speaker needed help with setting up a projector in our auditorium. He had a Mac, and I informed him that we do not provide the adapter needed to hooked Macs up to a VGA cable. We decided that if he moved his presentation (a .pptx file) to a flash drive, we should supply a PC for him to use. I then preceded to go search for a PC for him to use.

When I returned, he had already plugged his flash drive into my personal netbook, which runs openSUSE. The presentation was open in OpenOffice.org, and his complaint was that the formatting was wrong, not that the OS was in any way confusing.

So kudos to KDE for creating software that a stranger could pick up and use without my being there to guide him. I wasn't gone for long to look for a Windows computer with the latest Microsoft Office capable of running his .pptx for him, so KDE had to be familiar enough/intuitive enough for him to manage it on his own. I doubt he realized it wasn't Windows until I told him.