Yeah well the more important thing seems to be that they changed gnome-over-compiz setting to gnome 3.0 w/ gnome-shell, which means the compositing window manag

Yeah well the more important thing seems to be that they changed gnome-over-compiz setting to gnome 3.0 w/ gnome-shell, which means the compositing window manager is now part of the gnome. While some ideas in gnome-shell are quite cool (though obtainable in gnome 2.x as 3rd party stuff like gnome-do project), the stability on some GPU hw/firmware/driver configurations may be sucky. And if you care about your current gnome2+compiz configuration, it will be most probably messed by upgrading.