My SEO knowledge is limited, yet I could notice an important factor with Google. Google seems to give importance to the content that’s most recent. Infact, the recency seems to have a bit more weightage than the page rank. For example, when a fresh page is created that is optimized for a given keyword, a website (home page rank) that has a pagerank of 3 easily beat those that are as high as with pagerank 6 and 7. But as time passes, the page keeps getting demoted eventually returning to it’s right place considering the pagerank only effect.
So, essentially, Google’s search results seem to be based on
Freshness(page) + PR(page)
For the fresh pages for which I have seen this correlation, I had also had a Pagerank 4 based blog discuss it. So, it’s not clear if the Freshness is of the page in itself or if it’s related to the freshness of the link to the page. If it’s the later, then it’s important to realize that, since Google takes time to find your new page, index it, gradually promote it from it’s sandbox to the main search servers, there is a lag. That means, if you advertise a text link ad on a website, the result of it could be felt 10 to 30 days later.
Also, it’s unclear on the adverse impact of the page’s score if an inlink is removed. That is, I am not familiar if Google would take note of drop in the inlinks and immediately propagate it to the main index or if it waits for a while. If it drops immediately, then it’s better to extend the text link ad service beyond the one month. Essentially, in that case, set a side budget for 2 months and expect good results for only 50 to 30 days. So, even though the text link ads prove to be twice as much expensive, if it’s helping the site, then it’s worth it. I see that a lot of affiliates can benefit from this type of behavior of Google.
BTW, I recently read that Google no longer gives credit to domain names that contain ‘-‘ in them that are created specifically for SEO. I wonder if using an ‘_’ and in the url, for example, cordless power tools gets any extra credit or not.