I find myself agreeing with the article's authors on ebook pricing, much to my surprise. Certainly if the publishers fulfill their responsibilities, both to authors and to customers, there is justification for them getting their share of the profit.
However, it is amusing to note that one of the authors was from Random House Publishing Group. Random House recently floated their free ebook site
http://www.suvudu.com/freelibrary/ and one of their first offerings was His Majesty's Dragon by Naomi Novik. I got a copy of the ebook and compared it to the paperback I already owned. I was more than surprised to discover that the quality of the editing/proofreading of the ebook was far below the print version with quite a few simple errors in the ebook that were not in the print copy.
It is also interesting to look at the prices of another book in the series. The Throne of Jade, the second book in the series, is advertised at $7.99 on the Random House site for both paperback and ebook. The book is also available from Random House as an abridged audio download for $14.98 and unabridged audio download for $25.00. (Is it any surprise that Random House was one of the first publishers to disable TTS in their ebooks?) I paid $7.50 for the paperback at a bookstore, the paperback version is no longer available at Amazon except used but the ebook version sells for $6.39 and the hardbound version is $78.75 (The newest book in the series hardcover price is $16.50). Following the pricing guidelines proposed in the article the ebook version should be around $3.00-4.00 which seems more reasonable than the current ebook price if the editing/proofreading is up to snuff.
It is worth mentioning that Random House Publishing Group is a firm supporter of DRM and has been diddling with author's royalties with respect to ebooks of late. I don't buy ebooks from them but I'll take free ones.