No fallback mode in GNOME 3.8, future of gnome-panel

Does this mean you can no longer run xmonad or other tiling window managers with GNOME?

Could you before? I was under the impression that the shell is the window manager, Mutter.

In fallback mode, it was possible.

That's nice. Anyone still using GNOME will, I'm sure, appreciate it.

Sounds like a plan.