The author of the article, John Siracusa, began his life with ebooks with a job at Palm Digital Media back in 2002 and offers up a comprehensive history of the ebook market. I clearly remember reading Peanut Press books on my old Palm OS devices and still use eReader and Fictionwise for content on my mobile phones.
While I still have and read paper books from time-to-time (they are great for the beach or by the pool) I prefer taking along a dedicated ebook reader when I travel because I can carry multiple titles with me in a small package. As John points out, the argument for reading books on a screen is really irrelevant today where people read content on the computer screen for hours and hours without too much complaint.
I found his take on the Kindle interesting and agree that my phone is always with me and may actually serve as a better ebook reader for a couple of reasons. With the ebook readers on the iPhone and the large high resolution display, the iPhone may just be the "killer" ebook reader. As I have said before, if Apple would add ebooks to iTunes I think they would rival the Amazon Kindle in ebook sales and we would see an explosion of interest in ebooks.