Date: February 2, 2006
IBM announced a new service strategy for AIX. The objective is to increase the length of time you can run on an AIX Maintenance Level.
Currently, there are 2 ML's per year. Going forward, there will be one ML and one functional release per year. (The releases are 6 months apart.). The ML contains fixes, while the functional release contains new features. My understanding is that you should strive to maintain your system near the current ML. The functional releases are "as needed".
For more information, see the "services and support best practices" website at
February 2, 2006