GIMP 2.8.18

If you've only switched over to Gimp recently you should know that Gimp 2.8 is a big jump over 2.6 (2.7 was like the testing phase of 2.8). One major change is that Gimp has a single window mode that's similar to pretty much all of the graphics programs around. Other things included enhanced sliders, more brushes, layer grouping, cage transforming, a text box offering more text options, save image split into 2 options: save (gimp format) / export (jpg, png, bmp, tif, tga...) and more. One major change when using the X button to close Gimp basically closes everything at once and exits Gimp. Before, the X button was used to close the current image only.
For an offical log, follow this link to the Gimp site:

2.8.18 replaces version 2.8.16. The release note listed along with this update says this version fixes a 'vulnerability in the XCF loading code'. previously caused crashing in certain files and could allow arbitrary code from an attacker. Wouldn't want that!
In this release there are bug fixes and you can catch the list of updates here:
Gimp 2.9.4 is currently in the works. It's labelled as reliable for production work but has 'loose ends' that need tying. But quite a good amount of features have been added and are worth checking out:
Release date: 14 July 2016
Download it here:
Older Versions