"xdg-open is a shell-script which works independent from the desktop-environment. It will inspect your environment and if it can detect that you are running Gnome, KDE, XFCE or LXDE it will use the correct tool from your Desktop Environment (such as exo-open under XFCE). If it can't detect your environment it will try to open the file itself. "
Sergio,
Good read on xdg-open vs gnome-open etc. => http:// budts.be/ weblog/ 2011/07/ xdf-open- vs-exo- open
"xdg-open is a shell-script which works independent from the desktop- environment. It will inspect your environment and if it can detect that you are running Gnome, KDE, XFCE or LXDE it will use the correct tool from your Desktop Environment (such as exo-open under XFCE). If it can't detect your environment it will try to open the file itself. "