While its never easy to go from version to version, Vbulletin 3.0 forum software is much nicer and easier to navigiate. I believe this site is running V2.29.

For a shot of an active site running v3 see http://www.washingtonhockeyonline.com much cleaner and has integrated pull down menus. Plus an advanced message composer/editer.

 

Yeah, a lot of other forums I visit are using the latest version of vBulletin. It's not a big change from 2.29, but there are some differences that took me a while to get used to (a lot of advantages to 3.0).