About a month ago, I posed a question in the Q & A section of SEOmoz. THe question was: How does a website cross the threshhold from a PageRank 4 to a PageRank 5? A member of the SEOmoz staff answered that there is really no formula or set of criteria that will push a site from PR 4 to PR 5.

However, I'm not so sure I agree with that statement. While there probably is no exact algorithm that determines when a site will cross the P 4 barrier, I think that by examining PR5+ sites systematically, we can get some clues.

I've done quite a bit of study on sites that are PR5 or higher. I looked at many different factors including backlinks, content, usability, domain age, etc. In other words, all the basic and most common SEO factors. Although I haven't an exhaustive interpretation of why these sites score over PR 5, I have drawn some tentative conclusions.

After all the basic and intermediate SEO has been done on a site, it appears that crossing the PR barrier requires a few more somewhat intangible factors:

• A site must not only be usable, functional, have good architectural design, and have interactivity; it must also provide products and/or services which benefit a large number of web surfers.
• It appears a site must offer novel or innovative products and/or services; in other words, it must not merely offer services/products other sites offer, but unique products/services.
• It appears a site must receive a pretty significant amount of traffic, over a substantial period of time.
• It seems that a site must enhance and enrich the overall quality of web experience, knowledge, and/or communication; or, the site must offer a valuable social service, which many people, in authoritative circles, deem as valuable.
• Although I'm less certain of this, it appears that sites which break the PR 5 barrier seem to be created or run by representatives, businesses, or personalities who have achieved notoriety and/or special achievement in social media or some subset of the Internet community. For example, very often you will see these personalities or businesses referenced or quoted in places such as Wikipedia, or referenced in a book being sold on Amazon, etc.

These are just a few items I found which seem to be common elements of sites that break the PR 4 threshold. What the data suggest is that no amount of pure search engine optimization, by itself, will cause a site to break that threshold in itself. A website must do more. And the people who build and manage the site must have a fairly solid brand or name reputation in multiple Internet arenas.