Interesting look at what an 'unconference' might be as compared to a conference:

Conference vs Unconference

Attendees vs Participants
Exhibitors vs Participants
Recruiting speakers vs Recruiting participants
Content planning vs Content facilitation
Direct marketing vs Word of mouth marketing
Handouts vs Wikis
12 month planning cycle vs 12 week planning cycle
Top down vs Bottom up
Wisdom of experts vs Wisdom of crowds
Magazine coverage 2 months later vs Live blogging/podcasting
Slides vs Stories
Panels vs Conversations
Best practices vs Practicing