On GreenBiz.com, Matthew Wheeland writes that, though the iPad is "a green device, it isn't a planet-saver." He refers to the New York Times op-chart "How Green Is My iPad?" which says
If you order a book online and have it shipped 500 miles by air, that creates roughly the same pollution and waste as making the book in the first place. Driving five miles to the bookstore and back causes about 10 times the pollution and resource depletion as producing it. You'd need to drive to a store 300 miles away to create the equivalent in toxic impacts on health of making one e-reader -- but you might do that and more if you drive to the mall every time you buy a new book.
Another opinion piece cited says the iPad is environmentally friendly only after 18 books are read on it. Read the full article.