Comment 4 for bug 134682

Outputting to any directory, be it ~home or Desktop or some other arbitrary location, has been repeatedly seen by users as potentially dangerous, because files could be overwritten. The problem is that every user has a different idea of how this should be handled: some users would prefer getting job numbers automatically appended to all filenames, while others prefer keeping the document's original name and older versions of a similarly named document always being overwritten. This is how I came to the compromise of this ~/CUPS-PDF (previously ~/PDF) folder.

besides, let's put things in perspective: all 3 desktop environments supported by Ubuntu have their own printing system in place, which means that CUPS-PDF's only role on Ubuntu is as an "if all else fails" catch-all safety net. This is mainly useful for non-GNOME and non-KDE applications, such as Firefox or OpenOffice, that directly access CUPS back-ends rather that use e.g. gnomeprint as a printing front-end to CUPS.