Amazon appears to be trying to become for books what Apple is for music.  In seeking to be a one-stop-shop for book buyers, Amazon is expanding their Kindle line to include a larger version that is made for textbooks.
Both the Wall Street Journal and Reuters (piggy-backing on the WSJ story) are reporting that the official announcement will come Wednesday.  It will be interesting to see how supportive students and other stakeholders (like college bookstores and textbook publishers) will be of this venture, but I imagine that at some point electronic books are going to be the norm.  It appears that time might come sooner than I would have predicted just a few months ago.

Amazon Set to Offer Kindle for Textbooks. Geoffrey A. Fowler, Ben Worthen. Wall Street Journal. (Eastern edition). New York, N.Y.: May 5, 2009. pg. B.5

Bigger Kindle e-reader may not be a newspaper fix.  Reuters.  May 4, 2009.

Amazon’s Kindle is Off to College.  BusinessWeek.  May 4, 2009.