Apple has released OS X Mountain Lion. You can buy Mountain Lion now through the Vanderbilt Software Store under the Departments/More Software tab for $11.49. If you purchase through the Software Store (i.e. through Apple Volume Licensing), you can only install the OS on Vanderbilt owned Macs.
Before you upgrade, make sure your Mac can run Mountain Lion and that it is running the latest version of Snow Leopard (10.6.8) or Lion (10.7.x). Click the Apple icon at the top left of your screen, choose About This Mac, and then click More Information to find out your model and OS version. The following models support Mountain Lion:
•iMac (Mid 2007 or newer)
•MacBook (Late 2008 Aluminum, or Early 2009 or newer)
•MacBook Air (Late 2008 or newer)
•Mac mini (Early 2009 or newer)
•Mac Pro (Early 2008 or newer)
If you are not running the most current version of Snow Leopard, update to the latest version by clicking the Apple icon and choosing Software Update to install Snow Leopard 10.6.8 before upgrading to Mountain Lion.
You should also verify compatibility between Mountain Lion and your apps by going to http://softwarestore.vanderbilt.edu and clicking App Compatibility with Mountain Lion before you upgrade.