I know, I know. Everyone everywhere is running SEO interviews with everyone. But Bill Slawski Interview over at SEO Buzz Box is well worth a read. Aaron Pratt's got a great set of questions that he puts to Bill, who in turn has very clear, good responses that show how the original Google notion of links as votes has become complicated for both Google and search marketers.
I have a slide in my long-standing Intro To Search Marketing session I do at our SES conferences that bullet points a number of ways search engines might or might not count links these days, to help illustrate why you can't just depend on that old PageRank meter.
Bill's responses go beyond the bullet points, for those who want to dig deeper into some of the many patents and research papers that have been released. Bill, of course, covers patents for us on the blog. But if you're looking for a nice, concise catch-up piece with his thinkings out of patents from the past, give this article a read.