It was recently announced that GNOME 3.8 would not be including the GNOME 2 fallback mode. This had a lot of folks a bit concerned. Apparently it was used more than GNOME developers figured. Not wanting to go backwards, Matthias Clasen has thought of a way that may pacify users of the departing fallback mode.
Clasen posted to a GNOME mailing list today that he thinks using some community extensions to bring back GNOME 2-like features is the answer. He said exactly, "we have a pretty awesome extension mechanism in gnome-shell (extensions.gnome.org), and there are a ton of extensions out there which allow users to bring back many of the 'classic' UX elements."
rest here