I have just moved from f16 to f17 and can't get freenx-server working with gnome3.
After successful authentication, just the desktop background comes up without menus or status bars. The only option is to close the NX client window (NX Client for Windows 18.104.22.168) which gives a xmessage suspend, terminate, cancel pop-up.
I have tried setting COMMAND_START_GNOME to "/usr/bin/gnome-session --session=gnome-fallback" in /etc/nxserver/node.conf. This changes gets rid of the "GNOME 3 Failed to Load" error pop-up, but still no menu bars.
It was working on f16 (gnome-desktop3-3.2.1-2.fc16.x86_64 and freenx-server-0.7.3-23.fc16.x86_64).
My nx session log is attached