It's hard to tell when darkened UI elements and black or dark gray backgrounds became associated with "professional." While Apple's Aperture and Adobe's Lightroom are the best known proponents of the concept in image editing, they're certainly not the first pieces of software to bear the subdued look. Darkened graphics programs always seemed especially popular on "exotic" platforms like SGI and Amiga, and NeoChrome had a dark UI on Atari in the late 80s. These days most of Apple's "serious" applications are dark, or getting darker, and Adobe is close beside them.
Adobe just showed off a "sneak peak" of Photoshop CS6 on YouTube, which includes a darkened UI for "a more immersive experience." You can actually choose between four shades, with the lightest being the old look, and the darkest making everything nearly black. Of course, the age-old excuse of removing distraction and allowing you to "focus on the image" still applies, which just makes us wonder: why are lightened UIs are still the default in software design? And if a darkened UI is clearly superior, why did it take Adobe more than two decades to come around for its flagship product? Food for thought as graphic designers the world over begin lobbying their IT department for a rapid CS6 upgrade, and would-be graphic designers warm up BitTorrent.