Rick Latona said:
This is an interesting comment. What does a Google data center watch tool tell you and how is that information useful?
Ok, I'll try to explain this in an easy to understand way. Think of it like this...
When you go to
www.google.com, depending on your location you are redirected to a certain "datacenter" (the word I'll use for this example) in your country (aka - a special IP address.)
In the U.S. there are multiple (xx) Google IPs/datacenters/whatever you want to call thems.
So if you live in California you would go to datacenter X, whereas if you were in New York, you you would go to datacenter Y. And usually 15+ datacenters inbetween.
Now, the interesting part comes in when they are having a pagerank, backlink or similiar "update"... all these datacenters update at different times, and most importantly different results. Until they are completely settled all these datacenters will usually show different results. Some higher than the ending outcome, some lower. If you use a watch tool, you will see that the majority of the datacenters or IPs are doing different results with your domain, this can be helpful in determing what your future results/pagerank may look like. It takes a really good(experienced) eye to guess accurately sometimes.
This is just one of the things the average person wouldn't know, that someone that deals with these thing day in and day out would have knowledge of. In fact, when you hear the phrase "Google Dance" this is partially the reasoning behind why Google is "dancing" with your results/pageranks, because the datacenters are "fighting" in a way to push a certain result global over all the IPs. It becomes very predictable after a while if you are studying one domain and you can get a lot of knowledge.
One nice tool is
www.mcdar.net, but without a certain professional reading it, I wouldn't go planning the future off of what mcdar might show you.
In other words, they give you a good quess at what will happen with a domain in the future. But again, you need to know how to read them accurately. It could be useful if you were planning to buy someones website, and you looked at this to see that it was probably moving down in rank, you might change your mind.