Google has moved on big-time in the past few years. First, putting noticeable restrictions on spammers, and now to a potential death of inbound links. Companies across the world still base their SEO strategies on link building and I can't tell you how many times people approach me asking how to increase inbound links. Sure, Yahoo and MSN could still be living the early days where relevance of a site was determined by incoming links, but Google is developing something new and it could clearly be seen in their Information Retrieval Based on Historical Data patent (by the way, if you read through inventors of that patent, you'll see good-old Matt Cutts that's been buzzing around the net to my great annoyance). From the document:

A system identifies a document and obtains one or more types of history data associated with the document. The system may generate a score for the document based, at least in part, on the one or more types of history data.

With this patent Google is remodelling their search algorithm and the new age of search will be based on Clickstream. In other words, Google is now able to measure user behaviour on a website by tracking clickthroughs, cached items, history, etc. Google makes it clear that the way users behave while visiting your site after finding it through a search query reflects on the relevance of that site. I have absolutely no objections to that method. So what can you do get prepared for the new wave of search algorithms?

Create an inviting Description Meta Tag
While there are still some meta tag critics, I wan to encourage everyone to write a user friendly description tag. It doesn't have to contain your keywords, the sole function of it is to increase visitor CTR (click through ratio) when they see your result in their search.

Establish a solid content base
When a visitor find himself on your site, there needs to be information he/she was looking for. In other words, you mist write useful and compelling content to grab attention. This is where blogs are guaranteed to succeed, since it is a blogger's goal to write quality content.

Make your site user-friendly
There is no other way to convert visitors to regular readers other than making your site user-friendly. You should work on obvious navigation, good color scheme, and anything else that can be though of as attractive by a random visitor.

Make visitors want to bookmark your site
The patent hints that bookmarking can be though of as a measure of your site's relevance/importance. Make it easy for users to bookmark you and secure an extra returning visitor.

The path I've just described seems abstract and mathematically unfocused. Fortunately (or unfortunately for some of us) this seems to be the way Google is headed. Ranking a site based on how visitors behave on it is a very good estimate of that site's relevance and importance. For now, we all must think in terms of the future and work for things that are yet to come. Whatever it maybe, the only sure way to high rankings is quality work and product.

Additional Sources: Information Retrieval Based on Historical Data patent.