Innovation question
 

vBulletin 5 Connect is claimed to be the "world's leading community software", "the leader in online community software", with the "most advanced and comprehensive feature set" and "unparalleled capabilities for building community websites."

Off the top of my head I could think of IPB, Drupal, and ExpressionEngine as capable alternatives with a long track record for building online communities. So my question is: Where is the innovation in vBulletin 5 and what makes it better than the rest of the pack?