Key improvements of the GRASS 6.4.2 release include enhanced
portability for MS-Windows (native support), major fixes for the new
wxPython based portable graphical interface, and new functionality
(new network tools, zonal support for univariate statistics, image
processing improvements, GRASS Python Library extensions,
an embedded interactive Python Shell, an experimental Graphical
Modeler, and new Cartographic Composer front-end to ps.map).