Website Structure

[JJMcClure]

PR reduces not on the page but across the site. And whether it's algoPR or toolbarPR, a blogger can lose considerably by losing rankings / losing ad selling revenue as the case may be.

That would have been my assumption about the negative impact you're thinking of but I don't think it's true, losing PR won't affect the blog's ranking because PR isn't why pages rank. This blog page currently ranks 9th for the search phrase 'google instant' and it has lots of comments (all 'follow' links too) so it will:

1. Garner a lot of incoming backlinks therebye accruing more Site Authority and PR which internal pages will benefit from that much more than they'll lose out because of the PR they didn't get, which would have been minimal without all the incoming backlinks.

2. Not get any backlinks (it hasn't got any yet) and so it's PR will never improve and it couldn't be passing much to internal pages anyway.

Either way, the comments aren't hurting the ranking of that page, they're probably helping it by making it look useful, and will either help (by acquiring backlinks) or have no impact (it has no PR to pass on anyway) on the ranking of pages that page links to.

Also, since selling links that pass SEO benefit is against Google TOS I don't think that can be considered a negative impact eithers ince they'll nerf them if they idnetify them. Plus if the blog owner was selling links he'd know that lots of links on a page dilutes the quality of outgoing links, and that his customers would know that, and he'll be controlling the number of comments on his blog keeping them to a minimum. Again, this has no impact on his other pages.

I'm not seeing any way in which comments hurt our blog owner.

[hooperman]

That would have been my assumption about the negative impact you're thinking of but I don't think it's true, losing PR won't affect the blog's ranking because PR isn't why pages rank.

We all know that although "PR isn't why pages rank", PR is one factor in the ranking algo. If you reduce a factor used in ranking, then ranking is affected. I'm sure this was mentioned earlier in the thread:

We both know that pages don't rank well only because of PR

I don't believe anyone in this thread suggested that.

Nobody is asserting that pages rank because of one thing. They rank because of a number of things and PR is one of them.

[Clinton]

That PR isn't the only factor - something we've already been through - doesn't change the fact that it is a factor. Just because there are 200 factors in the algo doesn't mean that each one has an importance of exactly 1/200.

I'm not seeing any way in which comments hurt our blog owner.

I'm not seeing any way your dofollow blog example is remotely relevant. We're talking about the effect on blogs with nofollow comments.

[JJMcClure]

I'm not seeing any way your dofollow blog example is remotely relevant. .

Really? I dunno, I give up then. Maybe if you're still curious about this you might go onto a pure SEO forum and explain how leaving comments on a blog can cause that blog to "suffer considerably" , and see what the posters there say.

We're talking about the effect on blogs with nofollow comments.

At some point on this thread I posted a quote from Matt Cutts about how creating nofollow links (perhaps by leaving comments for example) basically has the same effect on your page PR as before nofollow was invented, which makes sense since both dilute your PR, so I gotta admit I've been posting on the assumption that nofollow was irrelevant to this discussion, my bad.

[Clinton]

how creating nofollow links (perhaps by leaving comments for example) basically has the same effect on your page PR as before nofollow was invented

I completely see, understand and even accept that this is likely the truth.

But before nofollow was invented that PR flowed somewhere - to the sites of the commentors. The more links outgoing links there were, the more PR was draining. When nofollow was introduced, bloggers naively just adopted it as standard for all comments and ceased to worry about the number of comments they were getting or the quality of the destination sites. Now most bloggers probably don't know it but by following the advice of the time and instituting nofollow they screwed themselves as there's a lot more juice draining out of their sites now than if they had never adopted nofollow in the first place.

Google changed the rules, the bloggers got screwed (a little bit). And they got screwed only because they believed whatever the Gorg told them and followed blindly.