Noah Wardrip-Fruin's draft of Expressive Processing: Digital Fictions, Computer Games, and Software Studies, which will be published by MIT Press, is undergoing an open peer-review process on the Grand Text Auto Weblog using a new plug-in version of CommentPress. The book is also undergoing a conventional peer-review process.
Read more about it at "Blog Comments and Peer Review Go Head to Head to See Which Makes a Book Better"and "Expressive Processing: An Experiment in Blog-Based Peer Review."
