We recently converted our boards from the terrible VBulletin 5 to XenForo, and the community are very happy and satisfied with everything. It's an almost 8 years old website, with a great history in the brazilian videogames market. With the VB5 we were almost like a zombie, but the XenForo brought the lights back!
Wordpress website: http://www.pxb.net.br
Xenforo boards: http://www.pxb.net.br/comunidade