Well done, I was interested in going for it, but knew the competition would be fierce. Think of all those pages that can be indexed by google now, I really didn't understand why they had banned all search engines from crawling the site.
I also thought they were an old version of phpBB, then saw Powered by: vBulletin down the bottom and wondered how old the version was haha.
Using robots file and/or robots meta tag:
<meta name="robots" content="noindex,nofollow"> tag.
Another way is by requiring you to have an account to view the forums.
Looking at domainstate they went with the robots option.
Yeah if it is just the robots meta tag, then every page you want to block.thanks mate.....if you go the robot option, must be on each page obviously and not just the index/home, right?