Well, it seems like I picked a bad week to minimize the effectiveness of social media as tools for organizing political protest against authoritarian regimes. In all fairness to both sides of the discussion, very few observers are arguing that social media alone can topple tyrants, and I was not saying that social media can not help in that effort. But proponents of social media as primary news and information sources during such events are likely to take comfort from the week's events in Tunisia.
Pending more thorough analysis, I still think that would be premature, not only because it's uncertain of how instrumental social media was, not in getting information out of Tunisia, but in circulating information within Tunisia.
But it's also not yet clear what the removal of former President Zine El Abidine Ben Ali represents in terms of the country's internal power dynamics. With the caveat that the following analysis is based on general political theory and second-hand analysis rather than a personal familiarity with Tunisia itself, for now, it resembles more an impeachment than a revolution. The Tunisian regime threw Ben Ali under the bus in order to preserve itself, but the regime itself remains a construction of Ben Ali's rule.