phpbb is rather awful could get many adult advertising postings from Russian poster bot. Does vbulletin also got this problem ? And has phpbb patch this weakness with their newest version ?
You can always start with PHPBB2 or 3 and then convert to vBulletin. It's always good to get started for nearly free and then migrate. In my case, I've run the free stuff and since I've got a money-making blog, I opted to go right to vBulletin. Success, Sam