The GIMP developers are proud to release GIMP 2.6.0
GIMP is the GNU Image Manipulation Program. It is a freely distributed piece of software for such tasks as photo retouching, image composition and image authoring. It works on many operating systems, in many languages. The most important change is a switch to GEGL engine (http://en.wikipedia.org/wiki/GEGL). By default the legacy 8bit code paths are still used, but a curious user can turn on the use of GEGL for the color operations with Colors / Use GEGL. I'm excited. I wonder how soon the the various plugins will be ported.
Release notes: http://gimp.org/release-notes/gimp-2.6.html
It features changes to the user interface addressing some often received complaints, and a tentative integration of GEGL, the graph based image processing library that will eventually bring high bit-depth and non-destructive editing to GIMP.
I just installed GIMP 2.6 and tried to open a 16 bit image and it converted it to an 8-bit image. The release notes says that GIMP has taken the initial steps towards integration with GEGL. I expect to see 16 bit implementation next year.
Binary packages for the various supported platforms should become available soon; please check the Downloads section