Google has changed a lot in the last few months.

I am generating SEO and back link reports for one of our long term clients that owns multiple web sites.

Now a days it is more difficult for even the best SEO experts, because Google has recently made this even more complex.

If a clients web site is penalized by Google it may still rank very well on Yahoo or MSN. The tough part is what causes Google to penalize a site is the exact reason that Yahoo and / or MSN may rank the site highly. Within the last two months Google has made many big changes. They completed the move to the Big Daddy database and implemented several new algorithms to:

1. Delete millions of pages from the Google database (cache). This has many ramifications to Google and to non Google webmasters. If a small webmaster has developed a newer site and has invested a lot of time developing good quality content and also has Google AdWords on these pages, it not only knocks the wind out of the smaller webmaster, it also hurts Google. Google loses ad revenue and losses its stature as the premiere search engine that indexes all excellent unique quality content.

The important factor to consider for my clients is:
if Google deleted a page or many pages on different urls that they have text links on...how does this effect them?

I believe Google analyzes your back link ratio and decides if your back links come from "good" or "bad" sites however complex the methods are Google chooses to define this. If you have too many back links from sites Google does not like you may be penalized. We can say you have a bad link ratio in Google's eyes. How can we know what Google likes or does not like?
Well if within the last 2 months pages that show up with having PR on the Google PR meter and are not in the Google cache. This means Google recently took these pages out of the Google database. They took them out either because they have to few back links or bad back links Google does not like. Either way you do not want links from these pages because they either do not help you with Google or may even penalize you with Google. Again here is the catch, if you get rid of these you lose the benefit they are giving you with MSN and Yahoo.

2. Even if a page is in the Google cache not all links are created equal. We have a database of over 2,000 high PR web sites that are in the Google cache and have been blocked from passing PageRank for over 2 years. This include most counter sites, major newspaper sites, major radio sites, etc. etc.

So what is a good link and what is a natural link?
How would Google define this?

We really do not know for sure, however it is wise SEO practice to consider these concepts. E.g. One would hope that if the whitehouse.gov placed a link to this web site it would count for maximum value with Google. We also know / believe Google breaks the values up on a scale to rate:

i) can a site pass PageRank? Does Google trust this sites "reputation"? also some sites appear to be able to pass partial PageRank. It used to be 6 months ago that a site either could pass PageRank or Not (binary), that is no longer the case.

ii) Google also looks at a sites "reputation" as being able to pass anchor text value.

So let's use a hypothetical extreme example to make this clear.

Apple.com a PR10 site links to your computer business and also to your friends pizza business web site.

We believe apple is not blocked from passing PageRank as they do not sell links and it would be extremely difficult and rare for apple to link to any site. We are just trying to illustrate our point here not debate the facts on every site. Anyway based on the points above would both the pizza site and the computer site receive the maximum PageRank power and full anchor text ranking power from Google?

We do not think so, of course we may be wrong.

We believe the computer business web site would receive maximum points from Google on both PageRank and anchor text values being passed.

We believe the pizza business web site would only receive partial value for PageRank being passed and little or no value for anchor text power being passed.

So the above is want our testing shows us to be the way Google works today. I hope this helps people understand and realize how amazingly complex Google is getting with this SEO stuff.