When I first looked at the permissions, it made me laugh. I mentioned it elsewhere, but I'm a linux developer, and often we communicate with other opensource developers (i.e. phpbb guys) in IRC.
Anyway, phpBB3's permission system was designed by linux lovers. The phpbb3 acl system models the postix acl's system in linux (enhanced permissions, not the normal xrwxrwxrw perms). ACL's in Linux are a pain to learn, but work great once you learn it. I laughed because I figured that the perms development team overlooked the fact that phpBB3 guys aren't necessary *nix guys. 😛
Trust me know, the system works great. The nice thing about this system is the ability to add new acl's to the structure (I know ... MORE CONFUSION). Well, once you learn the concept of acl's, you'll likely find the need to create more (i.e. view my self auth comments in some phpbb modding boards).
I just converted my board to phpBB3 and I LOVE IT. I do agree they overdid the permission settings but phpBB3 has so many features default that you would spend hours upon hours installing mods with phpbb2 and you still wouldn't get the functionality of phpBB3 :mrgreen:
RSS and a task manager i think also and some other stuff... I can't really remember what they said now. 3.2 is also only going to be php5 compatible also so there will be less code in all the files which is needed for php4 so it should preform better and php5 has alot more functions they can use when making 3.2.