Archive-It has released the The Web Archiving Life Cycle Model.
Here's an excerpt:
In order to address the lack of best practices and to increase awareness of the importance of web archiving as fundamental to digital preservation, the Archive-It team developed the Web Archiving Life Cycle Model (WALCM). This model is based on the team's experiences as well as lessons learned from countless partner institutions, including in-depth case studies of six of those institutions. The WALCM is an attempt to represent common workflows and create a measurable model for organizations to reference in order to create or improve their web archiving programs.