It looks like the latest Gimp will get a new GUI. The new single window mode will be a welcome addition. In the past, opening a graphic file in Gimp involves two or three separate windows. Now, the Tools and Layer menus are all going to be one window. Here is an excerpt from an article from the H.
With the release of developer version 2.7.1, GIMP users and early adopters have been given the opportunity to preview the new features of the free image editing software’s forthcoming stable 2.8 release. The most important improvement is the graphical user interface (GUI), which has undergone a thorough overhaul. For instance, it now includes a single-window mode which doesn’t display elements such as the tools or layers menus in separate windows next to the image window, instead lining these elements up alongside the image in the same window.