From the Book of Obvious, E-books are better for the environment than printed books. "The e-reader savings eclipse attempts by the publishing industry to reduce its damage to the environment through cleaner manufacturing processes and more recycling programs, the San Francisco-based research and consulting firm said in a report." If your not cutting down trees and processing them into books, it is frankly obvious that digital devices are more environmentally friendly than traditional printed media. Please tell me something I don't now.
Still, I doubt people are converting to e-readers for their environmental benefits. I see that more a a by-product. The reason is one of convenience of purchase, lighter load to "carry' multiple books, and even the me-too behavior that comes with electronic devices. Improving the environment is a good thing; this article simply states the obvious.