The lasting effect of Google’s publicly viewable PageRank score
http://searchengineland.com/rip-google-pagerank-retrospective-244286
Earlier this year Google announced that it would be removing its last vestige of publicly visible PageRank score after years of providing this feature. PageRank – “the secret sauce that Google used to become the giant of the search world” – provided a numeric rating of how important it considered a particular page to be. This score was widely flouted to be used in its search algorithm as a means of promoting itself as a smarter search engine.
By providing any user the ability to check their PageRank opened up a new field in search engine optimization (SEO) methods and allowed users to zero in on how to improve this score; thus, they were able to make their own websites more easily accessible. This ultimately led to the emergence of the link market in which networks developed, so as to allow people to buy oinks and potentially improve their PageRank. With any good market, however, there is always spam or junk and the link market was no different. Links popped up everywhere on the web creating considerably backlash at Google, and, despite taking action to try to stop it, link spam has continued since.
While publicly visible PageRank has been slowly disappearing from the web, the removal of the Google Toolbar in Internet Explorer (an already depreciated browser) is the final nail, so to speak, in the PageRank coffin. Unfortunately, the damage rendered is in some ways irreversible as the link market is already well in place. Even without an easy way to evaluate a link, they will continue to be brokered and spammed, plaguing the rest of the web notwithstanding the fact that PageRank is not the only factor that goes into how Google views a page.