My first article based on the Membership Communications Project dataset has just been published as the lead article in Policy & Internet, an online journal published by Berkeley Electronic Press and Oxford Internet Institute.
The article is titled “Online Political Mobilization from the Advocacy Group’s Perspective.” The article challenges the”clicktivism” critique of online organizing, as presented by Malcolm Gladwell, Micah White, Stu Shulman and others. Relying upon personal observations with the environmental movement and on a content analysis of 6 months of advocacy group e-mail traffic, I argue that e-petitions (1) are less heavily-used than many critics believe, and (2) are used by advocacy groups as an initial tactic in a broader strategy, including a “ladder-of-engagement” that leads to heavier volunteer involvement and further political actions.
You can download the article for free from BEPress, so I’m linking to it here rather than posting a copy on my site.
[UPDATE: Policy & Internet has moved from BEPress to Wiley. Since the old link no longer works, I’ve posted a working paper version of the article here.]
David Karpf 
Thank you for a very interesting paper. I have quoted from it in a post on my site on cyber-utopians v cyber-cynics (since we’re both using wordpress I think my username should automatically be a link to it – if not I can post an explicit url if you are interested.)