Link Metrics, Post PageRank

PageRank isn’t dead yet–but it’s slowly dying. Although many people still use PR as a rough metric when weighing the value of the link, certain developments lead me to believe that its days as the primary metric of the value of a link are over.

1) Toolbar PageRank is now only updated every three months
2) Most SEOs agree that its impact on the SERPs is now extremely limited
2) PageRank attempts to measure the "absolute" link power of a page, but certain algorithmic components (Topic-Sensitive PageRank [PDF], Hilltop) only reward sites that are linked from their topical community

This all begs the question: if we aren’t considering PageRank, what metrics should we use to guage the value of a link?

McMohan asks, "’What if’ Google were to pull down that greenbar from its toolbar?" in this thread at WMW:

My list would include these, in order of importance –

a. Alexa Rank (With all its anomalies)
b. SERPs that the site/page enjoys for its target keyword/s.
c. Quality IBLs if any (such as dmoz)

Although Alexa data is indeed shaky, we have reason to believe Google will soon be using traffic and user behavior data as a way to boost/devalue links and pages, and Alexa is the best source of that data freely available. Of course the page’s position in the SERPs would be ultra important in light of Topic-Sensitive PageRank [PDF alert] or Hilltop. Finally, quality IBLs such as DMOZ or .gov’s would certainly help a site gain "trust" in the eyes of a search engine (TrustRank [PDF]).

The downside is that it will now take more time and effort to figure out which links are good, and which are bad. We may even see "Ask yourself, ‘Is this good for my visitors?’" pop up more often in link building forums. White hats rejoice