It has a lot of features that compare with IPB and vBulletin. It has better looks, permissions capabilities, and now it does subforums. The old phpBB didn't do that. You can report posts, warn users for their conduct on the site, and now place temporary bans (not a feature in previous versions). It has a Moderator Control Panel where mods can ban, warn, investigate reported posts, etc. If you want a looksy, I found a link for a demo from phpBBhacks.com: