The Geospatial Modelling Environment (GME) is the predecessor of the Hawths Tools extension for ArcGIS. It is designed to facilitate rigorous spatial analysis and modelling by linking ArcGIS to the statistical software package R.
The new software has increased graphic ability in addition to batch processing, and records the workflow to ease replication.
One additional huge benefit with this new release is the ability to call on GME commands through Python.
More info here.
See also the documentation here.