Hmm, well, yes, I hear you: what for, why do that?
Just because ^^
Install xfce4-xfapplet-plugin from the universe repositories, then add it to the Xfce panel:
- Choose a GNOME applet to add:
- All done, the GNOME User Switcher is in place :)
Quoting the package description:
Description: Gnome applets plugin for Xfce panel
XfApplet is a plugin for the Xfce 4 panel. The plugin itself has no special functionality, its only purpose is to enable one to use Gnome applets inside the Xfce 4 panel just as they are used inside the Gnome panel.