The Faenza Icon theme is now supporting Gnome 3.2 and its installation in Ubuntu 11.10 is very simple, you need just to run a sequence of commands (PPA).
Faenza Icon Theme Installation
Open The terminal (Ctrl+Alt+T) and run these commands:
sudo add-apt-repository ppa:tiheum/equinox
sudo apt-get update
sudo apt-get install faenza-icon-theme
Enabling Faenza Icon Theme
If Gnome Tweak Tool is not installed, then use this command to install it:
sudo apt-get install gnome-tweak-tool
Launch Gnome Tweak Tool from the Unity Dash and head to the Theme tab, then select Faenza or its related themes from the "Icon theme" dropdown menu:
You can also select other Faenza themes (Faenza-Ambiance, Faenza-Dark, Faenza-Darker, Faenza-Darkest, Faenza-Radiance) which are also available in the dropdown menu. These themes are made to fit with dark or light menus, panels, and toolbars.
Here is my Desktop with the Faenza icon theme applied:
The Unity Dash:
Source: http://www.upubuntu.com/2011/11/how-to-install-and-enable-faenza-gnome.html