I hate vbulletin 5 with a passion. I think coding wise its sloppy and the style is horrible has over 600 css mistakes. I mean I write templating and css to 100% validity that should be the norm in the industry not put out crappy work. Then release some 1000 bug fix release.
Now you can read the discussion here about my progress.
Support for vBulletin 5
Basically I am just trying to tear down how they construct there page and see if we can offer header footer integration with this version.
I was able to grab the style and write up a template integration with relative ease but they construct there page way different and the $header $navbar $footer variables are no longer valid with this version which is how we called the stuff before and was able to offer an enhanced integration and wrap the header footer around our app.
The header footer is relatively a mock up I did just using the html page source of vb5.