These projects are almost diametrically opposite. GNOME tries to provide a very simple, solid but not very configurable desktop with good accessibility and stability while KDE tries to make a very configurable and powerful environment that can be customized to anyone’s needs. I don’t like KDE because it’s unstable, way too powerful for my personal needs (their “simple by default; powerful when needed” concept doesn’t really work) and I just don’t like the UI. Though KDE’s better performance is an objective advantage.