Teiid and Red Hat Products
Teiid was initially offered as an officially supported product called JBoss Enterprise Data Services Platform. That offering was later specialized to JBoss Data Virtualization. Now Data Virtualization will be available with Fuse Online (Syndesis) and Fuse Integration Services as part of a unified Red Hat Integration offering.
Teiid and MetaMatrix
MetaMatrix pioneered the EII (Enterprise Information Integration) market segment. Through many product iterations, the core of the MetaMatrix technology represents an advanced and proven approach to scalable information using a relational abstraction.
MetaMatrix joined Red Hat under JBoss Middleware in April of 2007. At the time MetaMatrix followed a closed source model. The MetaMatrix approach to EII continued as the community driven Teiid Project, with a subscription based product JBoss Enterprise Data Services Platform offering from Red Hat/JBoss.
The Teiid code line was started in parallel with the 5.5.2 release effort. The product and feature set of Teiid are different from MetaMatrix. Foremost Teiid encompasses only the MetaMatrix server and related components - the Designer is its own project at http://www.jboss.org/teiiddesigner. Next major components are evolving (Console -> JON) or have been removed (QueryBuilder). Finally important extension APIs have changed/and or been supplanted by other mechanisms. Please consult Teiid the release notes, documentation, and forums if you experience an issue migrating from MetaMatrix.