Yes, but Gnome seems to like to take over--I think some of their folks worked at MS first.
For example, if I'm running fluxbox, and then type nautilus, as a command in an xterm, it changes my entire desktop background to a default gnome background.
However, you can certainly run them both, usually using KDE and only booting into Gnome when necessary. There's usually a thingie to choose a session at login.
Linear Mode
