There were some obvious problems with integrating an essentially online group with a meat space meeting. When it came time for questions from the floor, the half of the audience attending electronically had a hard time getting recognized. It's not easy, online, to raise your hand or shout out from the back of the room. The offline crowd couldn't tell whether those who couldn't afford to travel to Santiago had views differing systematically from those who could. Because Robert's Rules of Order don't map well to a discussion list, many feel all too few have much to much to say.
Email filters can reduce time spent reading nonsense or flames.
If they watch only the physical meeting, they'll disenfranchise the online community. Every corporation also faces this new phenomenon, in its own way. No need to listen to the tedious speeches of those who can't really influence the decision but want to prove they were there. Instead of taking issues up in sequential order according to an agenda, spending only a limited amount of meeting time on each decision, the decision-making group can now proceed in parallel, taking as much time as necessary to make a group decision on each discussion thread. But we'll still have real meetings.