Tina Chrzastowski has self-archived "Assessing the Value of Ebooks to Academic Libraries and Users" in IDEALS.
Here's an excerpt:
In 2010, the University of Illinois at Urbana-Champaign (UIUC) Library agreed to take part in a global study of Elsevier electronic books (ebooks) sponsored by Elsevier Publishing. Ultimately, 129 UIUC faculty and graduate students participated in a logbook study that examined the ebook discovery process, detailed the way in which this group of researchers used ebooks, and queried users on the value they assigned to Elsevier ebooks. Going beyond the Elsevier survey, this study examines the value of ebooks both to UIUC users and to libraries, and it reports on an assessment of the ebook collection at UIUC including cost and use statistics. The results show that UIUC users assigned a high value to Elsevier ebooks for research purposes; this paper also determines that, in the broadest sense and as a collective format, ebooks offer libraries a better economic value than print books (pbooks) when comparing the cost of activities such as processing, circulation, storage and preservation.