Workspace cycling would be very nice in metacity (that is switching to the first workspace of the row when going right of the rightmost one and so on).
I know that metacity's philosophy is to keep things simple, and I agree that many things can be achieved through devilspie for instance, but workspace cycling realy needs to be at the wm level.
One of the reason I ask this is because some distros (I know this is the case of ubuntu but I'm not sure for other) use metacity for the "no desktop effect" mode and compiz for "desktop effect mode" and makes it transparent for the user (same theme, same keybindings, same number of desktop/workspaces,...).
This is all great despite that by going into "desktop effect" mode, the user magically gain desktop cycling which is'nt much of "fancy effect" and looses it when (s)he falls back to metacity.

I've implemented this feature for some months now and have tested it. It's really a very small amount of code. It's configurable by a gconf entry and was tested from early 2.21 to the 2.22. Patch attached hereafter.