The Eclipse Modeling Project focuses on the evolution and promotion of model-based development technologies within the Eclipse community by providing a unified set of modeling frameworks, tooling, and standards implementations.
Model based technologies leverage on having a common standard (EMOF/ECORE) to represent their data (models) and the implementation in Eclipse is the EMF Framework. There is a great adoption of this technology by the community and there are a lot of tools being built on top of the EMF Framework.
The need of creating tools (like editors, ...) allowing an easier editing of EMF models (more powerful than the default arborescent editor) becomes stronger day after day. The GMF Framework already provides an answer to this need in the specific case of graphical editors based on the EMF and GEF frameworks. The TMF framework also tackles this need by defining a concrete textual syntax for EMF metamodels.