Originally Posted by Robbie

Yeah, Pornhub can claim that they have SEO "geniuses" working for them.
But Google makes decisions about the relative importance of a site via the tags and text. We all use that...but then they look at how long a surfer stays on that particular site.

If they are only on your site a minute of two then you are ranked in that level of importance.
However if people are staying on a site for a long time then guess what? All things being equal...Google will go with the site that keeps the surfer longer.