Could Compiz start directly instead of replacing?

[Gianluca Cecchi]

I have setup startup of Compiz with fusion-icon inside session startup.
But is it possible now to avoid pre-load of metacity with replacement
by compiz each time and instead to load directly compiz as the initial
window-manager?
For example with a key in gconf? I saw in F9 the

/apps/gnome-session/rh/window_manager

that is currently set up to "metacity"
and is described as: Window Manager to start - The Window manager that
gnome-session will start. Valid values are "metacity" and "compiz"

Setting this should I also run fusion-icon at startup or not?
Anyone tried and got?
Is it a customized setting of fedora (see the "rh" inside the gconf
path)? What should be for a plain gnome the corresponding value in
that case?

Thanks,
Gianluca