The retina iMac is the dream computer for photographers. Adobe Lightroom is pretty much the only good option out there for powerful photo management. I bought the top-of-the-line retina iMac last year and Lightroom runs like garbage on it. Every scroll through thumbnails is jerky, every movement of any kind lacks fluidity. What gives? Please tell me you are working to utilize metal or something. This is so depressing. By the way, Aperture is smooth as butter on this thing. Shame it was abandoned.