This appears to be track lighting mounted to the bottom of the rafters. please consider using rail or cable systems in a setting like this. Available from Tech Lighting, WAC Lighting, LBL, and others. Available as line voltage, low voltage, and LED; all with a variety of heads and shades.

Thank you so much for your interest in our photograph. As we are a magazine representing builders, architects, designers, and more, we are unable to know the exact details of every project. I suggest you contact the home professional listed in the description of this photo. Thank you, CH+D mag

An exposed duct like that would sound like a neat idea to do. Well, before doing anything I guess my task would be to fix the ducts of my house. Those ducts sure have been giving me some trouble with the air conditioning. http://www.kleenaireservices.com/furnace_and_duct_cleaning.html