John Baez will give his Google Talk tomorrow in the form of a robot
johncarlosbaez.wordpress.com
johncarlosbaez.wordpress.com
Remind me to miss this.
I have doubts about whether or not it'll actually work without top-down coordination. At the very least, as long as it's cheap and easy for people to do stuff they want (e.g. drive somewhere), then they're free to do so. That won't change, unless it becomes not cheap anymore (could be any kind of not-cheap-state-of-being: gas tax, environmental restrictions, whatever).
Telepresence robots are useful, but I don't see the advantage of giving a speech with one over just using video chat as many others have done. Where Anybot might be useful is for the mingling before and after a speech.