Hi

I really wanted to know when and how often does Google update.

Thanks in advance.

Hi greatdaniel,
Google really has a mind of it's own... It use to spider a website about once per week on average, but it really would depend on the website's page rank and activity of the website. Youtube and twitter for instance are constantly spidered by google.
With the new Caffeine update the index will be updating much faster. The new update allows google to publish news almost in real-time.

As far as the search engine results page updating. I have seen google change things around throughout the day. between constant testing, customized search, and different datacenters, search results can change frequently throughout the day.

Hope that helps!

Thanks Matt for that very helpful information.

Thanks Matt for sharing that meaty piece of information.

Thanks Matt for sharing your wonderful ideas. I've really learned a lot from you.