The Rochester Public Library has an inventive use for the Kindle: the librarian loads it up with classics (free from Project Gutenberg and other sources). Handy substitute for an interlibrary loan and saves shelf space for books which may not circulate as much. Libraries will still need to purchase new translations or remarkable editions, depending on demand.
Several librarians have passed along the news that eReaders sit on the shelf once people have tested them and made a decision about whether to purchase. The classics solution gets a little more mileage and perhaps encourages readers to try a device. Great for lesser known Conrad, Bronte, Austen and L. Frank Baum. (Yes, many of the Oz books are at Project Gutenberg.)
Do add cataloging to the library database for every title on the eReader.