It's about

• What fun is
  
• Why some games are fun and some games are boring
  
• How different people respond to different kinds of fun
  
• What makes a game fun or not
  
• How games fit into the wider human culture
  
• Whether games can be art
  
• What degree of social responsibility game makers need to have
  
• How games can develop

At its core, though, it is about why games matter.