The Graphical Editing Framework (GEF) provides technology to create rich graphical editors and views. It is currently developed in two streams, namely:
The original project components Draw2d 3.x, GEF (MVC) 3.x, and Zest 1.x are still maintained but will not be developed further. Our main development effort is instead spent on building up the next generation components in terms of GEF4.
September 26, 2014 - Release 3.9.101 is available as part of the Luna SR1 simultaneous release (including Draw2d 3.9.101, GEF (MVC) 3.9.101, and Zest 1.5.101). Follow the Download link to obtain it. For further information about included features or bug fixes, please refer to the New and Noteworthy (3.9) page.
While the bulk of information about the GEF project can be found here, you may also consider the GEF Wiki as a source for further information.