The third book of the trilogy edited by Pat Harrigan and Noah Waldrip-Fruin, after “First Person: New Media as Story, Performance, and Game”, and “Second Person: Role-playing and Story in Games and Playable Media”, is out.
Henry Jenkins interviewed the authors, and the results are interesting, take a look
http://henryjenkins.org/2009/05/an_interview_with_pat_harrigan.html
http://henryjenkins.org/2009/05/authoring_and_exploring_vast_n.html
http://henryjenkins.org/2009/05/authoring_and_exploring_vast_n_1.html