I have a Mac in the office and PC in home.
Is there a way to tweak Fedora 16 with Gnome3 to use Mac-like keyboard switch shortcur? (Left win + Space)
The closest preconfigured one in Gnome 3 is Alt+Space.
Go to System Settings > Keyboard Layout > Layouts > Options ....
Expand the Key(s) to change layout menu and click the checkbox on the shortcut sequence you like the best.
See http://stackoverflow.com/questions/14172068/slow-keyboard-layout-switching-in-gnome-3-6 ... the point is that for switching keyboard layout just with modifiers you need to use gnome-tweak-tool.