This New York Times article details research regarding productivity versus screen size - is this the justification you're looking for?

http://www.collisiondetection.net/mt/archives/2005/10/meet_the_life_h.html

Mary Czerwinski first confronted this question while working, oddly

enough, in outer space. She is one of the world's leading experts in

interruption science, and she was hired in 1989 by Lockheed to help

NASA design the information systems for the International Space

Station.

...

...

The results? On the bigger screen, people completed the tasks at least 10 percent more quickly -- and some as much as 44 percent more quickly. They were also more likely to remember the seven-digit number, which showed that the multitasking was clearly less taxing on their brains. Some of the volunteers were so enthralled with the huge screen that they begged to take it home. In two decades of research, Czerwinski had never seen a single tweak to a computer system so significantly improve a user's productivity.