Basically nothing has changed but….
In all their wisdom the developers of Ubuntu have decided to leave the nvidia-settings out of the menus of previous Ubuntu versions after installing nvidia.
Crazy of course but in Ubuntu Hardy the Developers got wiser….
nvidia-settings is now a separate package.
So in Hardy if you use nvidia and nvidia-settings, also:
sudo apt-get install nvidia-settings
Oh and about nvidia-settings in the menu?
Its there now.