Simone Sacchi has self-archived "What Do We Mean by 'Preserving Digital Information'? Towards Sound Conceptual Foundations for Digital Stewardship."
Here's an excerpt:
Digital preservation is fundamental to information stewardship in the 21st century. Although much useful work on preservation strategies has been accomplished, we do not yet have an adequate conceptual framework that articulates precisely and formally what preservation actually is. The intention of the account provided here is to bring us closer to this goal. Following an initial analysis of the concept of preservation as it occurs in ordinary discourse around digital stewardship, several influential preservation models are analyzed, identifying both useful insights and problems. A framework of interrelated concepts is then developed that analyzes the challenges of long term digital stewardship through the lens of information communication.