Upgrading your current version of Cognos Analytics 11
You can upgrade your version of IBM® Cognos® Analytics by performing an "over the top" installation.
This is the default upgrade method, and the simplest and easiest way to upgrade. All components are upgraded to a newer version using the same configuration details, ports, themes and extensions as your previous installation.
The new and improved upgrade procedure takes advantage of the Cognos Analytics continuous delivery model, and deploys new features quickly and easily.
Detailed steps and a video can be found here: http://www.ibm.com/support/docview.wss?uid=swg21994915