For years, SEOs have engaged in a practice called Link Sculpting. Link sculpting is merely the idea that each page of your site has Page Rank and that page rank can be passed to other pages on your site or elsewhere on the Internet. Lets imagine PR points as currency. (Because it really is) If my Homepage has $20 worth of pagerank to invest and I have 20 outbound links on my site, it was common knowledge that Google would pass $1 worth of PR to each of the pages linked from that page. ($20/20=$1) A thoughtful SEO, however, could manipulate that PR currency to deep pages that he/she want to increase both the traffic and indexation rate. We could do this by “nofollowing” some of the links, telling Google NOT to follow the link, therefore making the existing links flow MORE Page Rank. Let me explain.
If my Page has $20 worth of PR and 20 links, we can assume the each page linked to will get one PR dollar. If I then NO FOLLOW 10 of those links, the balance of the PR cash will just average onto the rest of the links. Therefore the 10 links that remain as Follow will get $2PR each.
With this theory, and thousands of PR points to invest, I can “sculpt” my page rank to drive traffic and indexability to pages that might not otherwise see the Google light of day. It becomes a self fulfilling prophecy, because as these pages index, rank and create traffic patterns, (and inbound links) THEY earn PR points which in turn can we sculpted off to other pages in need… The entire site can be boosted, as it will have more indexed pages, a higher PR in general, more traffic, etc.
BUT NO MORE…
In a statement that rocked the SEO world, Matt Cutts, at SMX Advanced on June 3rd, stated that it is no longer effective to nofollow some pages in order to flow more Page Rank to the remaining followed pages. Basically, Matt stated (this is an example) that if your page has $20 worth of page rank and 20 links, 10 of which are no followed, the no followed links will still receive NO PR, but the remaining 10 followed links will only receive the $1PR each. In other words, nofollow links usurp PR, they just don’t pass it…
Here is a quote from Rand Fishkin, owner of SEOMoz,
“I’m saddened to say that given this change, we, as SEOs, are going to have to also recommend the best practice that comments (in all forms of UGC) no longer accept links. While Google has said that linking out to “good places” provides some value, that merely suggests that webmasters and site owners should select good resources editorially and link to them with live, followed links. Comments that contain links, unfortunately, will actively detract from a site’s ability to get pages indexed… ”
So who does this effect and does it effect you?
But if you have a decent sized site, with lots of PR and don’t know SEO really well, this conceivable could hurt. Frankly, I just dont understand why Google would do this. It seems really counter-intuitive to me.
Commenting and sharing community traffic IS web 2.0. If I can engage this community and leave a link that explains my credentials, that is cool. If I can carry the conversation back to “my place, even cooler. But a comment, without a link feels less authoritative to me. It loses some of its street cred, whuffie, social currency. I want to give the link to my commenters. I want my readers to know who is commenting on my site…and their authority within my community.
But until I hear a change in this policy, UNFORTUNATLY, my advise to my clients may have to be… “You just cant allow comment links until Google figures out the ramifications of this decision to our social media world, (and hopefully) reversed this decision.