I recently attended a meeting where the Chair justifiably concerned at the enormous cost, and renowned kittenish behavior of some of the attendees (er, me!), asked us all to close our notebooks to give the discussion our full, undivided attention. Denied access my external brain, I found the experience unusually stressful, and functioned quite badly. I recall saying "um", "er" and "ooh-ooh-agh" a lot. As anyone who has attended a W3C meeting will testify, being able to chat to others, take minutes and notes, record actions, ask for clarifications, paste in URI's, see who is on the phone, work out who is speaking or making noise, join the speaker's queue, conduct straw polls, crack jokes and heckle all over IRC makes for a far more productive meeting. Working together over a back channel is far better than giving the one person able to speak the unbroken gaze of a room full of folded arms and weary eyeballs. IOW what JP said and watch this space!