At long last, GIMP v2.8 to finally implement single-window interface
Good news to those of you who love the program but just couldn't adapt to the UI: version 2.8 will feature a selectable single window mode. As you can see in the mock-up above, it's a much more Photoshop-like experience. Hardcore GIMP fans, don't despair. If you've been convinced that multi-window mode is a superior way to work, you won't have to change.
GIMP developers have also been looking at ways of better handling multiple images in the editor. Tabs, of course, were added in Photoshop CS4. Don't expect to see them in GIMP 2.8, however. Peter Sikking offers three reasons in his blogs post that they have decided not to use tabs, instead opting for a movable thumbnail tray (image after the break).
Another idea being considered are "Polaroids" - floating, independent windows that can be used as references while working on an image in the editor. Apart from full images, you'll also be able to select a region and copy it to its own Polaroid - useful for doing detail work.