Importance:
Low
In a thread that asks if Google will sell their database of web site data, as Alexa is doing, GoogleGuy responds by quoting part of Google's privacy policy, with respect sharing data about users. Another member notes that this response does not address the question at hand - the selling of the actual web crawl data.
GoogleGuy Says: [
Link to quote]
I think our privacy policy covers pretty much all this. From http://www.google.com/privacy.html
(Brett, I think this is totally fine to quote--we want people to be informed about Google's privacy policies at all times. If you're worried, feel free to cut the quote and point people to the page.)
With Whom Does Google Share Information?
Google may share information about you with advertisers, business partners, sponsors, and other third parties. However, we only divulge aggregate information about our users and will not share personally identifiable information with any third party without your express consent. For example, we may disclose how frequently the average Google user visits Google, or which other query words are most often used with the query word "Linux." Please be aware, however, that we will release specific personal information about you if required to do so in order to comply with any valid legal process such as a search warrant, subpoena, statute, or court order.
I think that says it as well as I could. I highly encourage everyone to read our privacy policy--it's much more readable than you'd expect (only 8 short paragraphs!) and gives examples and everything.