Randal C. Picker has published "Private Digital Libraries and Orphan Works" in a special issue of the Berkeley Technology Law Journal about orphan works.
Here's an excerpt:
This Article is divided into three substantive parts. In Part II, this Article considers some of the characteristics that will matter for the competition between public and private digital libraries and offer a brief discussion of the emerging private digital libraries. Google's Book Search project is probably the most prominent example, but Amazon has an important initiative as well and there are many smaller examples. In Part III, this Article considers the current library exemptions in U.S. copyright law, with particular emphasis on § 108. . . .
In Part IV, this Article turns to the shape of a potential statutory licensing regime for orphan works.