Gnome Color doesn't work correctly with Nvidia driver.
If you want it to work as intended , you have to remove the Nvidia driver and replace by Nouveau. ( Check a lot of how-to on how to fall-back to Nouveau open-source driver ) Warning : Nouveau have for the moment weaker performances.
A solution to install a icc profile is to use http://dispcalgui.hoech.net : DispCalGUI
( you can download the Oneiric *.deb and install it into Precise if author don't have already packaged the new one, I tested it ). DispCalGUI is able to set a *.icc and create one with Nvidia driver and a colorimeter.
Note: for twinview/dualscreen/multiscreen ; it will apply only a single calibration profile on -both- screens. To set a different on each one, only Nouveau open-source driver can make it for the moment.