From their web site:
"Darkroom" is written for professional photographers who want to get the most out of Adobe's groundbreaking Photoshop Lightroom workflow application, and published 8 times a year by the National Association of Photoshop Professionals (NAPP). Each issue features in-depth tutorial articles, innovative digital photography techniques, and timesaving shortcuts written by the creative experts behind Photoshop User and Layers magazines.
"When you look at Adobe Photoshop Lightroom, you're looking at the future of the pro photographer's workflow, and a year or so from now if you're not using Lightroom, you're going to be left behind," said Scott Kelby, editor and publisher of Darkroom, NAPP president and the #1 top selling computer book author worldwide. "The integration between Lightroom and Adobe Photoshop CS2/CS3 creates the seamless, consistent, and efficient workflow that today's professionals need, and we launched Darkroom magazine to help these pros make the most of using these two amazing tools together."