Pretty interesting debate on BlogCritics between Kos Dozen member Jeff Seeman and blogger John Hawkins. I've seen online debates before in other contexts, and I think it works well as a forum. You don't get any kind of cues from body language or tone of voice, of course, which has its pros and cons. If debating online would increase the likelihood of opposing candidates engaging each other - and interested observers - then I'd say it's a win all around. Don't ask me to predict when the first such debate will occur, however.