Yeah, some variation of page rank is still the number one signal. That's why subdomain/subdirectory leasing at media companies is such a hot deal right now: you

Yeah, some variation of page rank is still the number one signal. That's why subdomain/subdirectory leasing at media companies is such a hot deal right now: you take completely unrelated content (e.g. coupons with affiliate links), throw them on a subdomain of a news site (e.g. CNN) and then just watch your content rank that would have never ranked on a "normal" domain. That "buying links" is the only deadly sin next to cloaking is more strong evidence for Google primarily relying on it. You don't get penalized for abusing Microdata, stuffing Emjois into your Title + Description or writing barely readable keyword-stuffed SEO texts, but get links from a well-known link-selling-site and watch your -100 penalty wreck your traffic.