I browsed to a forum I'd not been to for probably a good couple months today and noticed a layout change. I was pretty quickly able to identify the software as vBulletin 4, but I do believe this is one of the better implementations that I've seen so far. Hopefully Nick and crew won't mind, but the forum is DNForum.com - Welcome to DNForum.com (doesn't have the community that AA has, but I do realize the topics slightly overlap). Just thought I'd share because this is a pretty sizable forum. I do notice that the articles just seem slow.
It is actually quite nice. I must give kudos to them for keeping the default style but making it much more attractive by changing the forum and thread status icons, and editing the navbar. The homepage is quite nice, as well.
I must say that site looks great with vB4. I hope you don't mind me adding this site: WTF.com. They did a fantastic job with it.
In short: I do not like its design. It's far from simple and direct to the point. What's this forum about? Why this forum? Do I remember the forum style after visiting the forum for one minute? Do I remember the colors? No.
Horrible for me. Go to the forums. Dozens of "this is a normal thread" icons on the left on each thread. Lots of "this is a thread with unread messages" icons next to the "this is a thread with unread messages. go to the last unread post" icon. Horrible! Why am I reminded that I am in forum xx several times on the same page? Am I stupid? Do I forget about where I am the second I am reading the next line? I'll never understand designers who do that! Imagine a car with two displays "you are driving 50 km/h" next to "currently you are at a speed of 50 km/h". Unimaginable. And still the vbulletin 4 design is like that. Redundancy is all over vbulletin 4. There's no way to use vbulletin 4 design with only color changing - and there needs to be a lot to be done - you need to delete all the redundancy elements of at least the core templates navbar, forumhome, forumdisplay, showthread.