From Joomla! Documentation
The Joomla! Bug Squad (JBS) is a team within the Production Working Groups. Their job is to identify and fix bugs in Joomla. This includes the following:
- Scan the Joomla! Bug Reporting Forum and Joomla! 2.5 Bug Reporting Forum for reported issues and help community members with solving these issues.
- Maintaining the [Version 2.5x only Bug Tracker] and [Joomla 3.x Issue Tracker] .
- Fix reported bugs and resolve reported issues according to the Bug Tracking Process.
The Bug Squad is also supporting with testing and quality assurance when a new major or minor version is developed. Generally speaking the bug-squad is in the lead when a version switches from beta-stage to the stable-stage within the development cycle of Joomla!