These comments very rarely differentiate between toolbar PageRank and the PageRank of whatever kind Google stores on their servers and upgrades on an extremely frequent basis for every page. I know from first hand experience that the toolbar PageRank has very little to do with rankings, and is manually manipulated based on Google's commercial goals.

The Ranking Factors article at SEOmoz in many ways skirts around the issue, referring to Toolbar Pagerank, and then ignoring the concept of what is real PageRank by splitting things down into multiple related items.

• Link Popularity within the Site's Internal Link Structure
• Global Link Popularity of Site
• Topical Relevance of Inbound Links to Site
• Link Popularity of Site in Topical Community
• Global Link Popularity of Linking Site
• Link Popularity of Site in Topical Community
• Topical Relationship of Linking Site
• Internal Link Popularity of Linking Page within Host Site/Domain

The only direct question specific to PageRank was:-

• PageRank (as measured by the GG Toolbar) of Linking Page

Aaron Wall in answering this question actually gave a response hinting at the real importance of PageRank

The toolbar is perpetually outdated, but Google uses PageRank values to help set crawling priorities and to determine if a document should go in the regular or supplmental index.

• Can a page rank without a Title tag?
• Can a page rank without any internal linking?
• Can a page rank even on a new domain?
• Can a page rank without direct external links?

Ultimately with almost all the ranking factors, it is a balancing act, but with PageRank or however you wish to describe "Google Juice", it becomes a little more fundamental.

I realise if you take a purely theoretical stance, that if you created a 1000 page site full of original content, and then point Google to the sitemap for that site, that Google might index the whole site, and if you remove that link, some of the pages might remain indexed for a short or long period of time.
I haven't done the test, but a random surfer in theory could land on one of the isolated pages, if Google chose to keep the unconnected pages in the index.

I need a real world example to demonstrate how important juice flow around a website or blog is important, and I decided that Michael Martinez effectively was asking for this by saying:-

I do absolutely nothing to make SEO Theory SEO friendly. It is better indexed in Google than most SEO blogs.

Take that for what its worth.

I am always up for a challenge, especially when Michael went on to say

My complaints about the poor quality of Googles search results stem from Googles willful, deliberate segregation of the Web into two categories: Preferred Pages (Main Web Index) and Supplemental Pages. Preferred Pages are always shown first in search results regardless of how much more relevant the Supplemental Pages may be to queries.

Actually Google seems to have 3 types of pages

1. Main Index
2. Supplemental - apparently being phased out, but it could be all FUD, on that I agree with Michael on
3. Not Indexed

Michael forgot about the pages that are receiving so little juice, Google doesn't even bother indexing them, even on sites that are "better indexed than most SEO blogs".

It is possible that Michael is doing some kind of indexing test, or he could also have selectively decided that he doesn't want his old content in Google's index.
Thus I am not going to link directly to the following pages which would damage his test results.

That being said, Michael did ask to be quoted on it, and to quote him I am sure he would want the person doing the quoting to provide good, if not conclusive evidence for or against his stance. I am not going to claim conclusive evidence, but at least I have spent a little time on this reply.

Michael links to his date based archive pages from every page in his sidebar, thus they should be receiving a fair amount of juice. However that juice doesn't flow very deeply and he only has 5 posts on each page of his archives.

If you go just 3 pages deep, Michael starts to have indexing problems.

http://seo-theory.com/wordpress/2007/02/page/3/

Every article listed on that page is not in Google's index at all!

http://seo-theory.com/wordpress/2007/02/14/5-ways-to-launch-new-multiproduct/
Not Indexed By Google

http://seo-theory.com/wordpress/2007/02/13/yesterydays-seo-advice-at-todays-prices/
Not Indexed By Google

http://seo-theory.com/wordpress/2007/02/09/how-to-end-search-engine-slavery/
Not Indexed By Google

http://seo-theory.com/wordpress/2007/02/08/how-to-build-long-lasting-trusted-value/
Not Indexed By Google

http://seo-theory.com/wordpress/2007/02/07/best-kept-secrets-in-seo/
Not Indexed By Google

It seems the content on Michael's SEO Theory blog isn't as well indexed currently as you might expect, but as I mentioned earlier, that might be due to experimentation

I decided a while back it would be hard to write a post like this without having some pages of my own to point out, so I did a number of things.

• I didn't make extensive structure changes to improve things based on my Wordpress SEO articles
• I switched off translation plugins
• I don't include unique article descriptions
• When I upgraded to WP2.3, I didn't include Custom Query String, so my archives are not as flat as they used to be - I should note there are a few versions of CQS now available for WP2.3+ including Custom Query String Reloaded
• I have been using underscores with my tag_pages rather-than-dashes

I had a tough choice back in October, after being hit with a sizeable fake Toolbar PageRank penalty (currently -3) - continue making changes to my site structure to improve search engine performance, or keep the site relatively unchanged.

It is hard to say whether the penalties are/were material unless you bite the bullet and not make changes required by Google.

The only change I decided to make was to not include CQS when I upgraded to WP2.3+ - I decided that this would allow me to eventually provide some examples of pages falling out of the index, and then I would be able to demonstrate how I improve site structure to fix the problem.

With the changes Google made to the reporting of supplemental results, or if you believe them removing supplemental results altogether, it did take a little while for things to settle down.

I was waiting for a little deeper indexing activity to be visible, and then to wait a week or so for that activity to show in results. I did point out a few months ago that Google Webmaster tools provides these indexing charts, but the scales are still broken.

http://andybeard.eu/2007/01/mybloglog-social-networking-opportunity.html
Not In Google Index

The big difference is that I had to go back 7 pages in my January archives from last year to find a page that was no longer in the index, and my date based indexes are not on my sidebar on every page of this domain.
http://andybeard.eu/2007/01/page/7

Related links certainly help passing juice to older related content, but eventually even if you list 10 related pages, and use very specific control of related pages using a plugin such as Simple Tags, the related posts become superseded.
I will probably end up tagging this post seo, wordpress, linking, linking structures, pagerank, ranking factors

I have used most of those tags in the past, thus it is most likely that I will get 10 related posts, but also that some previously related posts will become displaced on the list, and that change will not just happen on this page, but all pages on this domain that are related.

Deep linking to older core content always brings a little fresh life back to them, and gives them a fresh injection of Google juice. Once you get to 500+ pages of content, it becomes harder and harder to give life back to all of them, and thus only what you class as "pillar" content gets a much needed burst of life.
There is a constant ebb and flow, 2 steps forward, one step back.

Maybe there are temporal factors taken into account by search engines, and some kind of temporary PageRank assigned to new content.
What I do know is that if content is buried deep in your archives, so deep that it doesn't receive any juice and isn't indexed, then a link from that page is totally worthless.
An old link on a TBPR PR10 domain that is buried deep in the archives might still have some value, whereas being 30 pages deep on a blog that receives very little link love, or maybe an archived forum post, isn't going to be worth much, if anything.

Google may remember old links that have lost juice for a period of time after they have been removed. Donna has spent some time looking into this.

If your pages aren't in Google's index, they can't rank for anything, even long tail queries.

To be in Google's index, pages really have to have a certain undefined amount of juice, no matter what other factors you gain merit for.

Thus PageRank is the primary Google Search Ranking Factor, because it is the only factor you 100% have to fulfil to have a chance for your pages to rank in Google's search results.

To give you a good parting analogy, all plants need water - different plants thrive with different amounts of water, and you can give a plant too much water - I don't know if you can have too much Google juice, but you might have too much over a short period of time a downpour which washes away the soil.

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