I thought that too, until I tried binding Super+T to launch a terminal in Gnome Shell. Turns out Unity eats all Super keypresses even when it's not running. On

I thought that too, until I tried binding Super+T to launch a terminal in Gnome Shell. Turns out Unity eats all Super keypresses even when it's not running. One workaround is to install CCSM, rebind the dash key to some key combo you'll never actually need, then set your key bindings normally. ...or install Xubuntu.