Future of books

What will the future holds for our beloved books? Do you think that we will still be reading books in 2050 the way we do today? To put things in perspective, I have researched the evolution of books:

12th century: The first book was produced by monks somewhere in Europe
1450: Gutenberg invents movable type in Europe, 400 years after Pi Sheng did in China, increasing supply to meet the increasing needs of university students
20th century: Lithography becomes widely used in book printing, allowing for an explosion in volume of books produced

My sense is that we are ready for another breakthrough. Surprisingly, e-books have been around for more than 30 years. Today, a few e-books reader start to get some air time in the news (the Amazon Kindle & the Sony Reader are the leading models). I just read that by 2018, more e-books could be sold than traditional books!

What do you think? Will e-books overtake traditional books the way digital songs are slowly winning the war over CDs? Are we missing something here?

Note: To access to more than 25,000 free e-books, check out the Project Gutenberg website. The project was launched in 1971 to digitize, archive and distribute cultural works. They don't spend time on the format of the pdf, which is a shame, but you can access most classics for free.