Google is it spidering?
 

http://www.google-dance-tool.com/

I have noticed a difference between the www. and the www2, data centers.

I thought it only spidered the beginning of each month?

The difference between the www. and the www2 I can see many times a week.

I never noticed that. I only notice search results shifting and traffic increasing/decreasing across various sites. And that usually happens the beginning of the month. For some reason some of my listings have recently shifted again

If you mean updating then yes its been happening for a couple of days now.you can see the new results on http://64.233.161.99

http://64.233.161.104 look at this results. This is the diffrence :)

I had sites with high listings completely vanish. At the same time sites with no presence before are getting 10k hits daily. Makes no sense. They most cut me off after so much :(