Struts was first released in June of 2001 and has become the de-facto standard for web application development. In December 2002 it was announced that WebWork and Struts Ti would join forces to become Struts Action Framework 2.0 and the official successor to Struts. In a new InfoQ article series, Ian Roughley looks at the task of moving applications from Struts to Struts2.
HostedQA, JIRA, Confluence, and Jive Forums all have implemented frameworks to manage changes to db schema's and data migrations between subsequent versions of their products. Pat Lightbody proposes that all enterprise apps should include an upgrade framework and provides some best practices.