This question comes from Boston. Eric Enge asks: „Do you think web search will ever make use of references (web site mentions that are not links) as a ranking signal?”.
So there's two answers. The first one is: “I never want to take a ranking signal off the table”, like I joked that if the phase of the moon can help us rank search results better, I'm willing to use the phase of the moon.
At the same time, think about how people would attack the use of references. Right now a lot of people rely on getting links. If all they have to do is have example.com in text, then you can leave that as comments all over the web and all over blogs and all over forums and it would almost be anywhere you could stamp any user generated content, people would be leaving those references.
So thats the sort of reason why you might be skeptical about why we'd use this sort of signal because people could abuse that sort of thing. They could just leave mentions of the URL, even if they can't generate links but I'll say we're willing to look at it, we would run the analysis, we would say “is there a way to pull out a signal from that noisy data?” where we could find a way to improve it.
It would definitely be the sort of thing were people would try to abuse it.