They even used to have a page that said:
Google does not censor results for any search term. The order and content of our results are completely automated; we do not manipulate our search results by hand. We believe strongly in allowing the democracy of the web to determine the inclusion and ranking of sites in our search results. To learn more about Googles search technology, please visit ...
Take a look at it now:
http://www.google.com/support/bin/answer.py?answer=17795&topic=368
(There's nothing there.)
Update: As jason points out, it now says:
It is Google's policy not to censor search results. However, in response to local laws, regulations, or policies, we may do so. When we remove search results for these reasons, we display a notice on our search results pages. Please note: For some older removals (before March 2005), we may not show a notice at this time.
i agree though, should have told china to fuck themselves