Jeroen, I agree! I tried to keep track of what happened at foss4g from my office in the Netherlands. The official website showed no changes during foss4g, IRC channels where pretty silent. My only source of information was twitter and because of the length of tweets, twitter only gave me "hints" about what was going on making me more curious!

During last summer State of the Map 2009 in Amsterdam, we had more then 50 people creating tweets, about 10 blogging live plus we had live video. The attendees at State of the Map where often live on IRC and with the video people at home could ask questions too!

Perhaps this is a good lesson for FOSS4G2010, make it more attractive for people who cannot attend.