Today i upgraded vBulletin on forums.bizhat.com to version Version 3.8.0. Upgrade was easy as normal, just upload new files, run upgrde script. There was some problem with vbseo, it need a patch applied to work.  Still vbseo is not supporting all new features of vbulletin 3.8, a new version is said to be released at the end of this month.