I use/support both Gnome and KDE. I have, until recently, primarily supported/installed Red Hat. Red Hat defaulted to and better supported Gnome so we generally went with that.
Over the last two years I have installed many systems which migrated both business and home users from Windows to Linux. Half stuck with the default Gnome on Red Hat; the other half got RH 7.3 with KDE or SuSE 9 with KDE. Some businesses had both classes or users. Most were running, pretty much, the same set of client sw (OpenOffice, Mozilla, file mgr, Gimp, ...) to perform similar tasks.
Those that received KDE desktops are very happy campers. They have migrated from using Windows to using Linux with very little problems and very little training. They are tickled (for the most part) with their Linux systems.
Those that received Gnome desktops are very UN-happy campers. Several find it so difficult and confusing they want their Windows systems back.
I understand the licensing argument (I think). I was more in favor of Gnome licensing but have been somewhat swayed by argument that KDE's GPL (give back) or QT license (support further development) may be better, in the long run, for the Linux community than Gnome's LGPL (free without having to give back).
I understand the desire to standardize on one desktop BUT feel a Gnome system, with no KDE support, does not really compete with the competition (Windows, OS-X, KDE, etc.). I appreciate the foundation may be better in some way, the app faster, etc. but if it does half of what I need a little faster or more elagantly it is still inadequate.
BUT, for me, the bottom line is my KDE users have been migrated easily and relatively painlessly and my Gnome users want their Windows back.