To everyone who is replying to the 8bit issue by mentioning GEGL - Have you actually used it in a professional capacity?
As a (now part-time) professional photographer, I have evaluated GIMP; and as a FOSS advocate I really wanted it to work. The performance issues the article mentions are with reasonable sized images at only 8 bits, but editing a 16bit, 25MP image wasn't just slow, it was unusable. Photoshop however, runs in near real time at these image sizes. Even automating a GEGL filter to run on a series of a few hundred images would take long enough that I couldn't maintain a usable workflow.
As a (now part-time) professional photographer, I have evaluated GIMP; and as a FOSS advocate I really wanted it to work. The performance issues the article mentions are with reasonable sized images at only 8 bits, but editing a 16bit, 25MP image wasn't just slow, it was unusable. Photoshop however, runs in near real time at these image sizes. Even automating a GEGL filter to run on a series of a few hundred images would take long enough that I couldn't maintain a usable workflow.