As we all know, Ubuntu developers have been gearing towards making it the Mac OS X of the Linux world. This is why we are seeing more and more Mac features landing in Ubuntu with each new version. While it might take a while for Canonical to make Ubuntu similar to (if not the same) as Mac, you can give your Ubuntu operating system the stylish Mac look with the FakeOSX theme.
Before we talk about the FakeOSX theme it is worth pointing out that this theme provides more of a generic Mac look for Ubuntu 11.10 and not specifically the Mac OS X Lion look. To get the Mac Lion look you can check out my guide: How To Make Ubuntu Look Like Mac OS X Lion.
Note: You can install the FakeOSX theme and follow the steps given in the MAC OS X Lion Guide to get the Mac Lion look for your Ubuntu desktop.
Coming back to the FakeOSX theme, it is a GTK 2/3 , Metacity theme, with the Gnome Shell theme. the process of installing this theme is similar to the installation of Gnome themes.
To install the FakeOSX theme, head over to the link given below, download the ZIP file and extract it to Home/Username/.Themes folder (create the directory if there is none). Launch the Gnome Tweak Tool and select the “FakeOSX” theme. For complete details regarding the installation of a Gnome theme, you can refer to the steps given in the instructions section of this post (How To Make Ubuntu Look Like Android 4.0 ICS). For more details about this theme, see the link given below.