I know that many GNOME users are reluctant to try KDE applications, but
there are several good ones that are better than their GNOME counterparts.
For years GNOME has included F-Spot, but it trashes your EXIF data and the
developers don't seem to care. Finally Ubuntu wised up and replaced it with
Shotwell, but unfortunately it is not quite ready for prime time, IMO.

DigiKam has been consistently a great application from day one. Another
great KDE app that many GNOME users should try is K3B (which is a burning
application, KDE Burn Baby Burn is what it is short for). I also prefer
Amarok to Rhythmbox, but that is more arguable since Rhythmbox is very good.
GNOME has nothing good for Usenet, but KDE has Klibido which works great.
Also Evince for GNOME is not nearly as strong as Okular (document viewer).

So GNOME users should not hesitate to colour outside the lines a bit. They
may like the results. The same could be said for KDE users. There are
several good GNOME apps that they should try (Cheese, GIMP, Dia to name a
few). Together GNOME and KDE are formidable. Separately they can be spotty.