IBM releases it's EMF Transformation language/engine

It's called Model Transformation Framework and in form it looks a lot like the QVT Partners MOF QVT submission (relations between things with multiplicities on the related model types). It support check and enforce, and has a bidirectional incremental execution paradigm. It also supports the ability to plug in implementations of arbitrary java that supports the engine, and this is the mechanism they use to support export of textual formats from a transformation.

At first glance all the boxes seem to be ticked. However, the examples provided are all very simple one-to-one transformations. It's not clear how they will support bi-directional transformations without some sort of default value assignments of the form that Compuware (and now the QVT Core) support. Also, it seems that objects always depend on other objects, which makes it difficult to do things like using unique name or integer values as the key to creating new objects. Once again, this may also only be a limitation of examples, not the language itself.