Tonight during a meeting I found that twitter was not a distraction. It actually facilitated communication with a colleague in another timezone who was looking in at the google docs we were working on.
The setup was straightforward two of us were generating a machinima script and the other was working on the formal gallery proposal. Our colleague in Australia who consented to edit the work later was watching us generate it and tweeting comments. These tweets were not task specific and did NOT distract us from our work. In fact those of us in the room were a much bigger distraction (curse youtube).